Main4-1, C# - rextester

Language: Layout:

//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
using ShuffleExtension;
using System.Threading;

namespace Rextester
{

public class Program {
        
        public int ratio1;
        public int ratio2;
        public int ratio3;
        public int num1, num2, num3;
        
        public static void Main(String[] args){
            //makeDivQ(500,999,10,99);
            //addLineBreak(30,2108);
            //makeDivQ(1000,9999,1,9);
            //makeDivQ(10,99,5,9);
            //makeAlgebra();
            //makeSubQ2by2(10,100,10,100);
            //makeFracQ();
            //makeDivQ(10,99,2,9);
            //makeDeciQ();
            multDivQ();
        }
        
        
        public static int Tens(){
         
            int rand = Rand.Next(0,2);
            
            if (rand==0) {
                
                return 10;
                
            }
            
            else 
                
                return 100;
               
        }

public static void multDivQ() {
            
            string title = "Multplication \\& Division (1)";
            List<string> multQ = new List<string>();
            for (int k=0; k<4; k++){
                    
                for (int i=2; i<=9; i++){
                                
                    for (int j=2; j<=9; j++){
                                   
                        if (multQ.Count()<200) multQ.Add("        \\item \\(\\mathmakebox[1.45cm][r]{"+i+"\\times"+j+"}=\\underline{\\hspace{2cm}}\\)"); //\\mathmakebox[1.45cm][r]{  
                    }   
                }   
            }
            
            List<string> divQ = new List<string>();
            for (int k=0; k<4; k++){
                
                for (int i=10; i<=100; i++){

for (int j=2; j<=9; j++){
                        
                        if (divQ.Count()<200 && i>j && i%j==0 &&i/j<10){divQ.Add("        \\item \\(\\mathmakebox[1.45cm][r]{"+i+"\\div"+j+"}=\\underline{\\hspace{2cm}}\\)");}
                        
                    }
        
                }
            }
            
            List<string> questions = new List<string>();
            //Console.WriteLine(multQ.Count());
            //Console.WriteLine(divQ.Count());
            
            questions.AddRange(multQ);
            questions.AddRange(divQ);
            questions.Shuffle();
            PrintArithmetic(questions, title);
            
        }

public static void makeMultQ(int lower1, int upper1, int lower2, int upper2) {
            
            string title = "Multplication  (1)";
            List<string> questions = new List<string>();
            for (int k=0; k<4; k++){
                    
                for (int i=lower1; i<=upper1; i++){
                                
                    for (int j=lower2; j<=upper2; j++){
                                   
                        questions.Add("        \\item \\("+i+"\\times"+j+"=\\underline{\\hspace{2cm}}\\)"); //\\mathmakebox[1.45cm][r]{  
                    }   
                }   
            }
            
            questions.Shuffle();
            
            PrintArithmetic(questions, title);
            
        }
        
        public static void makeDivQ(int lower1, int upper1, int lower2, int upper2) {
            
            string title = "Division (2 by 1 digits) General";
            List<string> questions = new List<string>();
            for (int k=0; k<4; k++){
                
                for (int i=lower1; i<=upper1; i++){

for (int j=lower2; j<=upper2; j++){
                        
                        if (i>j){questions.Add("        \\item \\(\\mathmakebox[1.45cm][r]{"+i+"\\div"+j+"}=\\underline{\\hspace{2cm}}\\)");}
                        
                    }
        
                }
            }
            questions.Shuffle();
            
            PrintArithmetic(questions, title);
            
        }
        
        public static void makeDeciQ(){
            
            string title = "Decimal Arithmetic General";
            // Division
            List<string> divQ = new List<string>();
            for (int i=0; i<6500; i++) {
                int tens = Tens();
                double argument = Math.Truncate(Rand.NextD(1.0,99.99)*tens)/tens;
                
                decimal num1 = Convert.ToDecimal(argument);
                int dividend = Rand.Next(2,1000);
                decimal result = dividend/num1;
                int count = BitConverter.GetBytes(decimal.GetBits(result)[3])[2];
                
                //Console.WriteLine(count);
                if(count<4 && divQ.Count()<120) {
                    //Console.WriteLine("{0}/{1}={2}", dividend,num1, dividend/num1);
                    divQ.Add("        \\item \\(\\mathmakebox[3cm][r]{"+dividend+"\\div"+num1+"}=\\underline{\\hspace{2cm}}\\)");
                }
                
                
            }
            
            //Multiplication
            List<string> multQ = new List<string>();
            
            for (int i=0; i<120; i++) {
                double number = Rand.NextD(1.0,99.99);
                int hund;
                double num1;
                if (number>=10) {
                    num1 = Math.Truncate(number*10)/10;
                    hund = 10;
                }
                
                else {
                    num1 = Math.Truncate(number*100)/100;
                    hund = 10;
                }
                
                double num2 = Math.Truncate(Rand.NextD(2,hund)*hund)/hund;
                double result = num1*num2;
                if ( (Math.Floor(num1)!=num1 || Math.Floor(num2)!=num2) && multQ.Count()<120) {
                    multQ.Add("        \\item \\(\\mathmakebox[3cm][r]{"+num1+"\\times"+num2+"}=\\underline{\\hspace{2cm}}\\)");
                }
            }
            
            //Add
            List<string> addQ = new List<string>();
            
            for (int i=0; i<120; i++) {
                double number = Rand.NextD(1.0,99.99);
                int hund = Tens();
                double num1;
                if (number>=10) {
                    num1 = Math.Truncate(number*10)/10;
                    //hund = 100;
                }
                
                else {
                    num1 = Math.Truncate(number*100)/100;
                    //hund = 10;
                }
                
                double num2 = Math.Truncate(Rand.NextD(2,hund)*hund)/hund;
                double result = num1+num2;
                addQ.Add("        \\item \\(\\mathmakebox[3cm][r]{"+num1+"+"+num2+"}=\\underline{\\hspace{2cm}}\\)");
            }
            
            //Subtract
            List<string> subQ = new List<string>();
            
            for (int i=0; i<300; i++) {
                double number = Rand.NextD(1.0,99.99);
                int hund = Tens();
                double num1;
                if (number>=10) {
                    num1 = Math.Truncate(number*10)/10;
                    //hund = 100;
                }
                
                else {
                    num1 = Math.Truncate(number*100)/100;
                    //hund = 10;
                }
                
                double num2 = Math.Truncate(Rand.NextD(2,hund)*hund)/hund;
                if(num1>num2) {
                    double result = num1-num2;
                    subQ.Add("        \\item \\(\\mathmakebox[3cm][r]{"+num1+"+"+num2+"}=\\underline{\\hspace{2cm}}\\)");
                }
                
            }
            List<string> questions = new List<string>();
            questions.AddRange(addQ);
            questions.AddRange(subQ);
            questions.AddRange(multQ);
            questions.AddRange(divQ);
            
            questions.Shuffle();
            PrintArithmetic(questions,title);
        }
              
        /*public static void makeDeciQ(double upper1) {
            
            string title = "Division (2 by 1 digits) General";
            List<string> addquestions = new List<string>();
            List<string> subquestions = new List<string>();
            List<string> multquestions = new List<string>();
            List<string> divquestions = new List<string>();
            string[] op = new string[4] {"+", "-", "\\times", "\\div"};

for (int i=1; i<=upper1; i++){
                
                int operand = Rand.Next(1,4);
                double[] num = new double[2] {Math.Truncate(Rand.NextD(1.0,99.99)*100)/100, Rand.Next(2,999)};
                
                decimal num1 = Convert.ToDecimal(num[1]));
                //if (operand==2){questions.Add("        \\item \\(\\mathmakebox[1.45cm][r]{"+num[0]+op[operand]+num[1]+"}=\\underline{\\hspace{2cm}}\\)");}
                    
                
                if (operand==4 && num[2]%num1==0){questions.Add("        \\item \\(\\mathmakebox[1.45cm][r]{"+num[0]+op[operand]+num[1]+"}=\\underline{\\hspace{2cm}}\\)");}
                    
                //else if (operand==1) {questions.Add("        \\item \\(\\mathmakebox[1.45cm][r]{"+num[0]+op[operand]+num[1]+"}=\\underline{\\hspace{2cm}}\\)");}
                //else if (operand==3) {questions.Add("        \\item \\(\\mathmakebox[1.45cm][r]{"+num[0]+op[operand]+num[1]+"}=\\underline{\\hspace{2cm}}\\)");}
            }
            
            //questions.Shuffle();
            
            //PrintArithmetic(questions, title);
            
        }*/
                                    
        public static void makeSubQ2by2(int lower1, int upper1, int lower2, int upper2){
                    
            string[] latex = new string[] {"\\fontsize{12pt}{16pt}\\selectfont", "        \\setlength\\itemsep{2em}"};
            
            string[] op = new string[2] {"(", ")("};
            string end =")=\\)";
            
            List<string> questions = new List<string>();
            
            for (int i=lower1; i<=upper1; i+=9){
            //for (int i=10; i<100;i++){
                
                for (int j=lower2; j<=upper2; j+=9){
                //for (int j=10; j<100;j++){   
                   
                    if (i!=j && i+j<100){questions.Add("        \\item \\(\\mathmakebox[1.45cm][r]{"+i+"-"+j+"}=\\underline{\\hspace{2cm}}\\)");}
                   /*if (i>j) {
                       
                       questions.Add("        \\item \\("+i+"-"+j+"=\\)");
                       
                   }*/
                   
                }
                
            }
            questions.Shuffle();
            
            //Console.WriteLine(questions.Count());
            
            Print(questions);
            /*for (int i=0; i<questions.Count(); i++){
                
                if(i==0){

Console.WriteLine("\\begin{figure}[ht!]");
                    Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                    Console.WriteLine("\\end{figure}");
                    Console.WriteLine();
                    Console.WriteLine("\\vspace{-15mm}\\begingroup");
                    Console.WriteLine("\\centering");
                    Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                    //Console.WriteLine("\\large Promatics Education Centre\\\\[1.5em]");
                    Console.WriteLine("\\endgroup");
                    Console.WriteLine();
                    Console.WriteLine(latex[0]);
                    Console.WriteLine("\\textbf{Exercise "+(i/30+1)+". "+exerciseTitle+".}\\\\");
                    Console.WriteLine("\\begin{multicols}{2}");
                    Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                    Console.WriteLine(latex[1]);

}
                Console.WriteLine(questions[i]);
               
                if (i!=0 && (i+1)%30==0){
                  
                    
                    Console.WriteLine("\\end{enumerate}");
                    Console.WriteLine("\\end{multicols}");
                    Console.WriteLine();
                    Console.WriteLine("\\pagebreak[4]");
                    Console.WriteLine();
                    Console.WriteLine("\\begin{figure}[ht!]");
                    Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                    Console.WriteLine("\\end{figure}");
                    Console.WriteLine();
                    Console.WriteLine("\\vspace{-15mm}\\begingroup");
                    Console.WriteLine("\\centering");
                    Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                    //Console.WriteLine("\\large Promatics Education Centre\\\\[1.5em]");
                    Console.WriteLine("\\endgroup");
                    Console.WriteLine();
                    Console.WriteLine(latex[0]);
                    Console.WriteLine("\\textbf{Exercise "+((i+30)/30+1)+". "+exerciseTitle+".}\\\\");
                    Console.WriteLine("\\begin{multicols}{2}");
                    Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                    Console.WriteLine(latex[1]);
                }
            }*/
        }
        
        public static void makeAlg(){
            
            int[] n = new int[10];
            
            for (int j=0; j<50; j++) {
                for (int i =0; i<n.Length; i++){
                    n[i] = Rand.Next(1,10);
                }
                char[] op = new char[] {'+','-'};
                int x = Rand.Next(0,2);
                int y = Rand.Next(0,2);
                int z = Rand.Next(0,2);
                Console.WriteLine("\\(\\dfrac{{{7}(x{4}{0})}}{{{1}}}{6}\\dfrac{{{8}(x{5}{2})}}{{{3}}}=\\)\\\\",n[0],n[1],n[2],n[3],op[x],op[y],op[z],n[4],n[5]);
            }

}

public static void makeQ(int lower1, int upper1, int lower2, int upper2){
         
            for (int i=lower1; i<=upper1; i+=9){

for (int j=lower2; j<=upper2; j+=9){

Console.WriteLine("        \\item \\("+i+"\\operation"+j+"=\\)");                   
            
                }
              
            }

}
        
        public static void makeFracQ(){
        
            string title = "Algebra Simplification Introduction";
            string exerciseTitle = "Simplify the algebraic expressions";
            int m=0;
            int i_final=30000;
            int incre= 0;
            
            string[] latex = new string[] {"\\fontsize{12pt}{16pt}\\selectfont", "        \\setlength\\itemsep{2em}"};
            string mathbox = "\\mathmakebox[1.45cm][r]{";
            string[] op = new string[2] {"(", ")("};
            string end =")=\\)";
            
            List<string> questions = new List<string>();
            
            
            //for (int i=lower1; i<=upper1; i+=9){
            for (int i=1; i<100;i++){
                
                //for (int j=lower2; j<=upper2; j+=9){
                for (int j=10; j<100;j++){   
                    
                    int num1 = Rand.Next(1,10);
                    int num2 = Rand.Next(1,10);
                    int denom1 = Rand.Next(2,10);
                    int denom2 = Rand.Next(2,10);
                    int mixed1 = Rand.Next(0,10);
                    int mixed2 = Rand.Next(0,10);
                    
                    if (num1!=denom1 && num2!=denom1 && num1<denom1 && num2<denom1){questions.Add("        \\item \\("+mixed1+"\\dfrac{"+num1+"}{"+denom1+"}+"+mixed2+"\\dfrac{"+num2+"}{"+denom1+"}=\\underline{\\hspace{2cm}}\\)");}
                   /*if (i>j) {
                       
                       questions.Add("        \\item \\("+i+"-"+j+"=\\)");
                       
                   }*/
                   
                }
                
            }
            questions.Shuffle();
            
            //Console.WriteLine(questions.Count());
            
            for (int i=0; i<questions.Count(); i++){
                
                if(i==0){

}
                Console.WriteLine(questions[i]);
               
                if (i!=0 && (i+1)%30==0){
                  
                    
                    Console.WriteLine("\\end{enumerate}");
                    Console.WriteLine("\\end{multicols}");
                    Console.WriteLine();
                    Console.WriteLine("\\pagebreak[4]");
                    Console.WriteLine();
                    Console.WriteLine("\\begin{figure}[ht!]");
                    Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                    Console.WriteLine("\\end{figure}");
                    Console.WriteLine();
                    Console.WriteLine("\\vspace{-15mm}\\begingroup");
                    Console.WriteLine("\\centering");
                    Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                    //Console.WriteLine("\\large Promatics Education Centre\\\\[1.5em]");
                    Console.WriteLine("\\endgroup");
                    Console.WriteLine();
                    Console.WriteLine(latex[0]);
                    Console.WriteLine("\\textbf{Exercise "+((i+30)/30+1)+". "+exerciseTitle+".}\\\\");
                    Console.WriteLine("\\begin{multicols}{2}");
                    Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                    Console.WriteLine(latex[1]);
                }
            }
        }
   
        /*public static void makeDivQ(int lower1, int upper1, int lower2, int upper2){
            
            for (int i=lower1; i<=upper1; i++){
  
                for (int j=lower2; j<=upper2; j++){
                  
                    if (i%j==0) { 
                       
                        Console.WriteLine("\\("+i+"\\div"+j+"=\\)");

}
                    
                }
               
            }
             
        }*/

public static void makeAlgebra(){
        
            string[] vari = new string[24] {"a","b","c","d","f","g","h","k","m","n","p","q","r","s","t","u","v","w","x","y","z","\\delta", "\\epsilon", "\\phi"};
            //var[0] = "a";
            //var[1] = "b";
            //var[2] = "c";
            
            int n=-1; // n is the random number of variables per question
            int m=0;
            int i_final=30000;
            int incre= 0;
            string title = "Algebra Simplification Introduction";
            string exerciseTitle = "Simplify the algebraic expressions";
            string[] latex = new string[] {"\\fontsize{12pt}{16pt}\\selectfont", "        \\setlength\\itemsep{2em}"};
            
            string[] op = new string[2] {"(", ")("};
            string end =")=\\)";
            for (int i=1; i<=i_final; i++) {

int num2=Rand.Next(0,3);  // range of number of different variables per question
                int num = Rand.Next(2,5); // range of number of total variables per question
                int consts=Rand.Next(1,6); // range of coefficients of the variables
                
                if(i==1){

Console.WriteLine("\\begin{figure}[ht!]");
                    Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                    Console.WriteLine("\\end{figure}");
                    Console.WriteLine();
                    Console.WriteLine("\\vspace{-15mm}\\begingroup");
                    Console.WriteLine("\\centering");
                    Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                    //Console.WriteLine("\\large Promatics Education Centre\\\\[1.5em]");
                    Console.WriteLine("\\endgroup");
                    Console.WriteLine();
                    Console.WriteLine(latex[0]);
                    Console.WriteLine("\\textbf{Exercise "+(m/30+1)+". "+exerciseTitle+".}\\\\");
                    Console.WriteLine("\\begin{multicols}{2}");
                    Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                    Console.WriteLine(latex[1]);

}

if (n==-1){ //first variable of each question
                    Console.Write("        \\item \\(");
                }
                
                if (n==0){
                Console.Write(consts+vari[num2+3*incre]+op[0]);
                
                }
            
                else if (n>0 && n<num){
                    Console.Write(consts+vari[num2+3*incre]+op[1]);
                }
                n++;                
                if (n==num){ 
                    m++;
                    Console.Write(consts+vari[num2+3*incre]);
                    Console.Write(end);
                    Console.WriteLine();
                    
                    if (m%30==0) {
                        incre=Rand.Next(0,8);
                        Console.WriteLine("\\end{enumerate}");
                        Console.WriteLine("\\end{multicols}");
                        Console.WriteLine();
                        Console.WriteLine("\\pagebreak[4]");
                        Console.WriteLine();
                        Console.WriteLine("\\begin{figure}[ht!]");
                        Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                        Console.WriteLine("\\end{figure}");
                        Console.WriteLine();
                        Console.WriteLine("\\vspace{-15mm}\\begingroup");
                        Console.WriteLine("\\centering");
                        Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                        //Console.WriteLine("\\large Promatics Education Centre\\\\[1.5em]");
                        Console.WriteLine("\\endgroup");
                        Console.WriteLine();
                        Console.WriteLine(latex[0]);
                        Console.WriteLine("\\textbf{Exercise "+(m/30+1)+". "+exerciseTitle+".}\\\\");
                        Console.WriteLine("\\begin{multicols}{2}");
                        Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                        Console.WriteLine(latex[1]);
                    }
                    
                    Console.Write("        \\item \\(");
                    n=0;
                }
                
                else if (n>num){
                    m++;
                    Console.Write(consts+vari[num2+3*incre]);
                    Console.Write(end);
                    Console.WriteLine();
                    
                    if (m%30==0) {
                        incre=Rand.Next(0,8);
                        Console.WriteLine("\\end{enumerate}");
                        Console.WriteLine("\\end{multicols}");
                        Console.WriteLine();
                        Console.WriteLine("\\pagebreak[4]");
                        Console.WriteLine();
                        Console.WriteLine("\\begin{figure}[ht!]");
                        Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                        Console.WriteLine("\\end{figure}");
                        Console.WriteLine();
                        Console.WriteLine("\\vspace{-15mm}\\begingroup");
                        Console.WriteLine("\\centering");
                        Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                        //Console.WriteLine("\\large Promatics Education Centre\\\\[1.5em]");
                        Console.WriteLine("\\endgroup");
                        Console.WriteLine();
                        Console.WriteLine(latex[0]);
                        Console.WriteLine("\\textbf{Exercise "+((m+30)/30+1)+". "+exerciseTitle+".}\\\\");
                        Console.WriteLine("\\begin{multicols}{2}");
                        Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                        Console.WriteLine(latex[1]);
                    }
                    
                    Console.Write("        \\item \\(");
                    n=0;
                }

/* if(i==i_final){
                    Console.WriteLine("\\end{enumerate}");
                    Console.WriteLine("\\end{multicols}");
                    
                }*/

}
            
            
        }
        
     
        public static void makeDiv4by2()     {
            
            for (int i =0; i<10000; i++) {
                  
                int dividend = Rand.Next(1001,10000);
                int divisor = Rand.Next(11,99);

if (dividend%divisor==0) {
                Console.WriteLine("        \\item \\("+dividend+"\\div"+divisor+"=\\)");
                    
                }
            }
        }
        
        public static void makeSciNot(){
            
            for (int i=0; i<100; i++){
                
                int num1 = Rand.Next(1,10);
                int dec1 = Rand.Next(1,10);
                int num2 = Rand.Next(1,10);
                int dec2 = Rand.Next(1,10);
                int exp = Rand.Next(-9,10);
                int plusminus = Rand.Next(-1,2);
                if (num1>num2 && exp != exp+plusminus){
                    
                Console.WriteLine("        \\item \\({0}.{3} \\times 10^{{{2}}}+{1}.{4} \\times 10^{{{5}}}=\\)",num1,num2,exp,dec1,dec2,exp+plusminus);
                }
            }
        }
        
        public static void DN(){
            
            //st<string> sign = new List<string>(new string[] {"+","-","*","/"});
            List<char> sign = new List<char>(new char[] {'+','-','*','/'});
            
            for (int i=0;i<100;i++){
                
                string question = "{0}{1}{2}{3}{4}{5}{6}";
                int pick1= Rand.Next(0+sign.Count());
                int pick2= Rand.Next(0+sign.Count());
                int pick3= Rand.Next(0+sign.Count());
                int num1=Rand.Next(-9,10);
                int num2=Rand.Next(-9,10);
                int num3=Rand.Next(-9,10);
                int num4=Rand.Next(-9,10);
                string num1_str, num2_str, num3_str, num4_str;
                bool num1_b = num1<0;
                bool num2_b = num2<0;
                bool num3_b = num3<0;
                bool num4_b = num4<0;
                
                if (num1_b && !num2_b && !num3_b && !num4_b) {
                    num1_str = "("+num1.ToString()+")";
                    Console.WriteLine(question,num1_str,sign[pick1],num2,sign[pick2],num3,sign[pick3],num4);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                    
                }
                
                else if (num2_b && !num1_b && !num3_b && !num4_b){
                    num2_str = "("+num2.ToString()+")";
                    Console.WriteLine(question,num1,sign[pick1],num2_str,sign[pick2],num3,sign[pick3],num4);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num3_b && !num1_b && !num2_b && !num4_b){
                    num3_str = "("+num3.ToString()+")";
                    Console.WriteLine(question,num1,sign[pick1],num2,sign[pick2],num3_str,sign[pick3],num4);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num4_b && !num1_b && !num2_b && !num3_b){
                    num4_str = "("+num4.ToString()+")";
                    Console.WriteLine(question,num1,sign[pick1],num2,sign[pick2],num3,sign[pick3],num4_str);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num1_b && num2_b &&!num3_b && !num4_b){
                    num1_str = "("+num1.ToString()+")";
                    num2_str = "("+num2.ToString()+")";
                    Console.WriteLine(question,num1_str,sign[pick1],num2_str,sign[pick2],num3,sign[pick3],num4);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num1_b && num3_b && !num2_b && !num4_b){ 
                    num1_str = "("+num1.ToString()+")";
                    num3_str = "("+num3.ToString()+")";
                    Console.WriteLine(question,num1_str,sign[pick1],num2,sign[pick2],num3_str,sign[pick3],num4);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num1_b && num4_b && !num2_b && !num3_b){
                    num1_str = "("+num1.ToString()+")";
                    num4_str = "("+num4.ToString()+")";
                    Console.WriteLine(question,num1_str,sign[pick1],num2,sign[pick2],num3,sign[pick3],num4_str);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num2_b && num3_b && !num1_b && !num4_b){
                    num2_str = "("+num2.ToString()+")";
                    num3_str = "("+num3.ToString()+")";
                    Console.WriteLine(question,num1,sign[pick1],num2_str,sign[pick2],num3_str,sign[pick3],num4);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num2_b && num4_b && !num1_b && !num3_b){
                    num2_str = "("+num2.ToString()+")";
                    num4_str = "("+num4.ToString()+")";
                    Console.WriteLine(question,num1,sign[pick1],num2_str,sign[pick2],num3,sign[pick3],num4_str);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num3_b && num4_b && !num1_b && !num2_b){
                    num3_str = "("+num3.ToString()+")";
                    num4_str = "("+num4.ToString()+")";
                    Console.WriteLine(question,num1,sign[pick1],num2,sign[pick2],num3_str,sign[pick3],num4_str);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num1_b && num2_b && num3_b && !num4_b){
                    num1_str = "("+num1.ToString()+")";
                    num2_str = "("+num2.ToString()+")";
                    num3_str = "("+num3.ToString()+")";
                    Console.WriteLine(question,num1_str,sign[pick1],num2_str,sign[pick2],num3_str,sign[pick3],num4);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num1_b && num3_b && num4_b && !num2_b){
                    num1_str = "("+num1.ToString()+")";
                    num3_str = "("+num3.ToString()+")";
                    num4_str = "("+num4.ToString()+")";
                    Console.WriteLine(question,num1_str,sign[pick1],num2,sign[pick2],num3_str,sign[pick3],num4_str);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num1_b && num2_b && num4_b && !num3_b){
                    num1_str = "("+num1.ToString()+")";
                    num2_str = "("+num2.ToString()+")";
                    num4_str = "("+num4.ToString()+")";
                    Console.WriteLine(question,num1_str,sign[pick1],num2_str,sign[pick2],num3,sign[pick3],num4_str);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else if (num2_b && num3_b && num4_b && !num1_b){
                    num2_str = "("+num2.ToString()+")";
                    num3_str = "("+num3.ToString()+")";
                    num4_str = "("+num4.ToString()+")";
                    Console.WriteLine(question,num1,sign[pick1],num2_str,sign[pick2],num3_str,sign[pick3],num4_str);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
                
                else {
                    Console.WriteLine(question,num1,sign[pick1],num2,sign[pick2],num3,sign[pick3],num4);
                    Console.WriteLine(num1+sign[pick1]+num2+sign[pick2]+num3+sign[pick3]+num4);
                }
              
            }

}
        
        public static void MixedNum() {
                       
            int[] n = new int[10];
            List<string> questions = new List<string> ();
            
            /////////////////// for the strings
            List<string> lines = new List<string>();
            lines.Add("\\begin{figure}[ht!]");
            lines.Add("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
            lines.Add("\\end{figure}");
            lines.Add("");
            lines.Add("\\begin{addmargin}[21em]{0em}");
            lines.Add("\\vspace{-26mm}Name: \\underline{\\hspace{5cm}} \\\\[0.5em]");
            lines.Add("\\end{addmargin}\\vspace{5mm}");
            lines.Add("");
            lines.Add("\\vspace{-10mm}\\begingroup");
            lines.Add("\\centering");
            lines.Add("\\LARGE Revision \\\\[0.5em]");
            lines.Add("\\endgroup");
            lines.Add("");
            lines.Add("\\section{What numbers (from 2 to 9) can these numbers be divisible by?}");
            lines.Add("\\begin{tasks}(2)");
            ///////////////////////

while (questions.Count()<300) {
                    //n[0] = Rand.Next(10,400); // for prime factorization
                    
                    n[0]=Rand.Next(3,8);
                    n[1]=Rand.Next();
                    
                    
                    for (int i =0; i<n.Length; i++){
                        n[i] = Rand.Next(1,13);
                        n[1] = Rand.Next(2,13);
                        n[3] = Rand.Next(2,13);
                        n[4] = Rand.Next(2,10);
                        n[5] = Rand.Next(2,10);
                    }
                    string[] op = new string[] {"+","-"};
                    int x = Rand.Next(0,op.Count());
                    int y = Rand.Next(0,2);
                    int z = Rand.Next(0,2);
                    //Console.WriteLine("\\("+n[4]+"\\dfrac{"+n[0]+"}{"+n[1]+op[x]+n[5]+"\\dfrac{"+n[2]+"}{"+n[3]+"}=\\)\\\\");
                    if (n[1]!=n[3] && n[0]<n[1] && n[2]<n[3]) {
                        double n0 = (double)n[0];
                        double n1 = (double)n[1];
                        double n2 = (double)n[2];
                        double n3 = (double)n[3];
                        if (op[x].Equals("-")){
                            if(n[4]>n[5]) {
                            
                            questions.Add("    \\task \\("+n[4]+"\\dfrac{"+n[0]+"}{"+n[1]+"}"+op[x]+n[5]+"\\dfrac{"+n[2]+"}{"+n[3]+"}=\\underline{\\hspace{2cm}}\\)\\\\");
                            }
                            else if (n[4]==n[5] && ((double)n[0]/(double)n[1])>((double)n[2]/(double)n[3])){
                                questions.Add("    \\task \\("+n[4]+"\\dfrac{"+n[0]+"}{"+n[1]+"}"+op[x]+n[5]+"\\dfrac{"+n[2]+"}{"+n[3]+"}=\\underline{\\hspace{2cm}}\\)\\\\");
                            }

}
                        
                        else  {   
                            questions.Add("    \\task \\("+n[4]+"\\dfrac{"+n[0]+"}{"+n[1]+"}"+op[x]+n[5]+"\\dfrac{"+n[2]+"}{"+n[3]+"}=\\underline{\\hspace{2cm}}\\)\\\\");
                        }
                     
                 // for fraction arithmetic 
                    
                    }
                    
                    
                }

int counter=0;
                            int increment=29;
                for (int i=0; i<questions.Count(); i++) {
                
                    
                
                    if ((i)%30==0){
                        //foreach (string line in lines) {
                                    
                            //Console.WriteLine(line);
                      Console.WriteLine("Begin");
                        //}
                    }
                  
                    Console.WriteLine(questions[i]);
                        if( i==increment) {
                        
                        //Console.WriteLine("\\end{tasks}");
                        //Console.WriteLine("\\newpage");
                        Console.WriteLine("End");
                    }  
                
                    increment = increment + counter*30;
                    counter = counter+1;
                    
                }
                
                            
                            //Console.WriteLine(questions.Count());

}
        
        public static void PrintArithmetic<T>(List<T> list, string title) {
        
        //string title = "Title ()";
        //string exerciseTitle = "Instructions";
        //int m=0;
        //int i_final=30000;
        //int incre= 0;
        
        string[] latex = new string[] {"\\fontsize{16pt}{25pt}\\selectfont", "        \\setlength\\itemsep{10pt}"};
        
        string[] op = new string[2] {"(", ")("};
        //string end = ")=\\)";
        
        for (int i=0; i<list.Count(); i++){
                    
                    if(i==0){
    
                        Console.WriteLine("\\begin{figure}[ht!]");
                        Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                        Console.WriteLine("\\end{figure}");
                        Console.WriteLine();
                        Console.WriteLine("\\vspace{-15mm}\\hspace*{-10mm}\\begingroup");
                        Console.WriteLine("\\centering");
                        Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                        Console.WriteLine("\\endgroup");
                        Console.WriteLine();
                        Console.WriteLine(latex[0]);
                        //Console.WriteLine("\\textbf{Exercise "+(i/30+1)+". "+exerciseTitle+".}\\\\");
                        Console.WriteLine("\\begin{multicols}{2}");
                        Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                        Console.WriteLine(latex[1]);
    
                    
                    }
                    Console.WriteLine(list[i]);
                   
                    if (i!=0 && (i+1)%30==0){
                      
                        
                        Console.WriteLine("\\end{enumerate}");
                        Console.WriteLine("\\end{multicols}");
                        Console.WriteLine();
                        Console.WriteLine("\\newpage");
                        Console.WriteLine();
                        Console.WriteLine("\\begin{figure}[ht!]");
                        Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                        Console.WriteLine("\\end{figure}");
                        Console.WriteLine();
                        Console.WriteLine("\\vspace{-15mm}\\hspace*{-10mm}\\begingroup");
                        Console.WriteLine("\\centering");
                        Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                        Console.WriteLine("\\endgroup");
                        Console.WriteLine();
                        //Console.WriteLine("\\textbf{Exercise "+((i+30)/30+1)+". "+exerciseTitle+".}\\\\");
                        Console.WriteLine("\\begin{multicols}{2}");
                        Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                        Console.WriteLine(latex[1]);
                    }
                }
        }
        
        public static void Print<T>(List<T> list) {
        
        string title = "Title ()";
        string exerciseTitle = "Instructions";
        //int m=0;
        //int i_final=30000;
        //int incre= 0;
        
        string[] latex = new string[] {"\\fontsize{12pt}{16pt}\\selectfont", "        \\setlength\\itemsep{2em}"};
        
        string[] op = new string[2] {"(", ")("};
        //string end = ")=\\)";
        
        for (int i=0; i<list.Count(); i++){
                    
                    if(i==0){
    
                        Console.WriteLine("\\begin{figure}[ht!]");
                        Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                        Console.WriteLine("\\end{figure}");
                        Console.WriteLine();
                        Console.WriteLine("\\vspace{-15mm}\\begingroup");
                        Console.WriteLine("\\centering");
                        Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                        Console.WriteLine("\\endgroup");
                        Console.WriteLine();
                        Console.WriteLine(latex[0]);
                        Console.WriteLine("\\textbf{Exercise "+(i/30+1)+". "+exerciseTitle+".}\\\\");
                        Console.WriteLine("\\begin{multicols}{2}");
                        Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                        Console.WriteLine(latex[1]);
    
                    
                    }
                    Console.WriteLine(list[i]);
                   
                    if (i!=0 && (i+1)%30==0){
                      
                        
                        Console.WriteLine("\\end{enumerate}");
                        Console.WriteLine("\\end{multicols}");
                        Console.WriteLine();
                        Console.WriteLine("\\newpage");
                        Console.WriteLine();
                        Console.WriteLine("\\begin{figure}[ht!]");
                        Console.WriteLine("\\vspace{-23mm}\\hspace*{-23mm}\\includegraphics[scale=0.9]{Logo.jpg}");
                        Console.WriteLine("\\end{figure}");
                        Console.WriteLine();
                        Console.WriteLine("\\vspace{-15mm}\\begingroup");
                        Console.WriteLine("\\centering");
                        Console.WriteLine("\\LARGE "+title+" \\\\[0.5em]");
                        Console.WriteLine("\\endgroup");
                        Console.WriteLine();
                        Console.WriteLine(latex[0]);
                        Console.WriteLine("\\textbf{Exercise "+((i+30)/30+1)+". "+exerciseTitle+".}\\\\");
                        Console.WriteLine("\\begin{multicols}{2}");
                        Console.WriteLine("    \\begin{enumerate}[label=\\arabic*)]");
                        Console.WriteLine(latex[1]);
                    }
                }
        }
        
         public static void LCM(int a, int b) {

int lcm;

int a_r=a;
             int b_r=b;
             int d=max(a_r,b_r);
             
             while(d>1) {
                 
                 if (a_r%d==0 && b_r%d==0) {
                     
                     int a_r_temp=a_r/d;
                     int b_r_temp=b_r/d;
                     a_r=a_r_temp;
                     b_r=b_r_temp;
                     lcm=d*a_r*b_r;
                     break;
                     
                 }
               
                 d--;

}
             
             lcm=d*a_r*b_r;
             Console.WriteLine("LCM({0},{1}): {2}", a,b,lcm);
         }
             
             
            
        public static void LCM(int a, int b, int c) {
     
            int lcm;
                
            if (a==0) {
                Console.Write("LCM("+a+","+b+","+c+") = ");
                LCM(b,c);
            }

else if (b==0) {
                Console.Write("LCM("+a+","+b+","+c+") = ");
                LCM(a,c);
            }
            
            else if(c==0) {
                Console.Write("LCM("+a+","+b+","+c+") = ");
                LCM(a,b);
            }
            
            // if all three are equal
            
            else if (a==b && b==c) {
            
                Console.WriteLine("LCM: "+a);
 
                
            }
            // if a and b are equal
            else if (a==b && a!=c) {
                if (a>c) { // if a is greater than c, use a as divisor then decrement
                    for (int i=a; a>1; i--) {
                        if (a%i==0 && c%i==0) {
                            int a_reduced=a/i;
                            int c_reduced=c/i;
                            lcm = i*a_reduced*c_reduced;
                            Console.WriteLine("LCM("+a+","+b+","+c+"): " + lcm);
                            break;
                        }
                    }
                }
                else { // if c is greater than a, use c as divisor then decrement
                    for (int i=c; c>1; i--) {
                        if (a%i==0 && c%i==0) {
                            int a_reduced=a/i;
                            int c_reduced=c/i;
                            lcm = i*a_reduced*c_reduced;
                            Console.WriteLine("LCM("+a+","+b+","+c+"): " + lcm);
                            break;
                        }
                    }
                }
            }
            // if b and c are equal
            else if (b==c && a!=b) {
                if (a>b) { // if a is greater than b, use b as divisor then decrement
                    for (int i=a; a>1; i--) {
                        if (a%i==0 && b%i==0) {
                            int a_reduced=a/i;
                            int b_reduced=b/i;
                            lcm = i*a_reduced*b_reduced;
                            Console.WriteLine("LCM("+a+","+b+","+c+"): " + lcm);
                            break;
                        }
                    }
                }
                else { // if b is greater than a, use b as divisor then decrement
                    for (int i=b; b>1; i--) {
                        if (a%i==0 && b%i==0) {
                            int a_reduced=a/i;
                            int b_reduced=b/i;
                            lcm = i*a_reduced*b_reduced;
                            Console.WriteLine("LCM("+a+","+b+","+c+"): " + lcm);
                            break;
                        }
                    }
                }
            }
            // if a and c are equal
            else if (a==c && a!=b) {
                if (a>b) { // if a is greater than b, use a as divisor then decrement
                    for (int i=a; a>1; i--) {
                        if (a%i==0 && b%i==0) {
                            int a_reduced=a/i;
                            int b_reduced=b/i;
                            lcm = i*a_reduced*b_reduced;
                            Console.WriteLine("LCM("+a+","+b+","+c+"): " + lcm);
                            break;
                        }
                    }
                }
                else { // if b is greater than a, use b as divisor then decrement
                    for (int i=b; b>1; i--) {
                        if (a%i==0 && b%i==0) {
                            int a_reduced=a/i;
                            int b_reduced=b/i;
                            lcm = i*a_reduced*b_reduced;            
                            Console.WriteLine("LCM("+a+","+b+","+c+"): " + lcm);
                            break;
                        }
                    }
                }
            }
                    
            //if all three are different
            else { 
                
                int a_r = a;
                int b_r = b;
                int c_r = c;

int d = max (a_r,b_r,c_r); //set divisor as the max of the 3 numbers
                
                while (d>1) {

if (a_r%d==0 && b_r%d==0 && c_r%d==0) {
                        
                        int a_r_temp=a_r/d;
                        int b_r_temp=b_r/d;
                        int c_r_temp=c_r/d;
                        a_r = a_r_temp;
                        b_r = b_r_temp;
                        c_r = c_r_temp;
                        //Console.WriteLine("a_r and b_r and c_r");
                        break;
                        
                    }
                    
                    else if (a_r%d==0 && b_r%d==0) {

int a_r_temp=a_r/d;
                        int b_r_temp=b_r/d;
                        a_r = a_r_temp;
                        b_r = b_r_temp;
                        //Console.WriteLine("a_r and b_r");
                        break;
            
                    }
                        
             
                    else if (a_r%d==0 && c_r%d==0) {

int a_r_temp=a_r/d;
                        int c_r_temp=c_r/d;
                        a_r = a_r_temp;
                        c_r = c_r_temp;
                        //Console.WriteLine("a_r and c_r");
                        break;

}
                        
                  
                    else if (b_r%d==0 && c_r%d==0) {

int b_r_temp=b_r/d;
                        int c_r_temp=c_r/d;
                        b_r = b_r_temp;
                        c_r = c_r_temp;
                        //Console.WriteLine("b_r and c_r");
                        break;

}
                   
                    else {
                                       
                        //lcm=d*a_r*b_r*c_r;
                        //Console.WriteLine("{0}, {1}, {2}, {3}",a_r,b_r,c_r,d);
                        //Console.WriteLine("LCM({0},{1},{2}): {3}",a,b,c,lcm);
                    
                    }
                    
                    d--;
                    
                }
                    
                
                        lcm=d*a_r*b_r*c_r;
                        //Console.WriteLine("{0}, {1}, {2}, {3}",a_r,b_r,c_r,d);
                        Console.WriteLine("LCM({0},{1},{2}): {3}",a,b,c,lcm);
            }
        }

public static int max(int a, int b) {
            
            if (a>b){
                return a;
            }
            else if (b>a){
                return b;
            }
            else {
                return a;
            }
        }

public static int max(int a, int b, int c) {

if (a>=b && a>=c) {
                
                return a;
            }
            
            else if (b>=a && b>=c) {
                 
                return b;
            }
            
            else {
                
                return c;
            }
        }

public static void Pyth(int lowerBound, int upperBound) {
            //Your code goes here
                       
            for (int i=lowerBound; i<=upperBound; i++) {
                
                for (int j=lowerBound; j<=upperBound; j++){
                    
                    double c = Math.Sqrt(Math.Pow(i,2)+Math.Pow(j,2));
                    if (c%1==0){
                        
                        Console.WriteLine("(a,b,c) = (" + i + "," + j + "," + c + ")");
                    }
                }
            }
        }
        
        public static void areaTrapezoid(double top, double bottom, double height) {
            
            double area = (top+bottom)*height/2;
            Console.WriteLine("Area: {0}", area);
    
        }

public static void volumeCylinder ( double radius, double height) {
            
            double vol = radius*radius*Math.PI*height;
            Console.WriteLine("Volume: {0}", vol);
        
        }

public static void sAreaCylinder(double radius, double height) {
            
            double s_area = 2*calcAreaCircle(radius) + calcAreaCircle(radius)*height;
            Console.WriteLine("Surface Area: {0}", s_area);
        }

public static void Circumf(int radius){
            
            double circ = 2*radius*Math.PI;
            Console.WriteLine("Circumference: {0}", circ);
        }
                
    
        public static void areaCircle(double r){
            double area = r*r*Math.PI;
            Console.WriteLine("Area: {0}", area);
        }
        
        public static double calcAreaCircle(double r){
        
            return r*r*Math.PI;
    
        }
        
        public static double calcCircumCirlce(double r){
            
            return 2*r*Math.PI;
        }
    
        public static void sAreaCone(int r, int l) {}

public static void volumeCone(int r, int h){}

public static void SimplifyRatio(int ratio1, int ratio2, int ratio3) {
            
            int divisor;
            if (ratio1>ratio2 && ratio1>ratio3) {
                divisor = ratio1;
             }
            else if (ratio2>ratio1 && ratio2>ratio3) {
                divisor = ratio2;
            }
            else divisor = ratio3;

int ratio1_reduce = ratio1;
            int ratio2_reduce = ratio2;
            int ratio3_reduce = ratio3;
            while (divisor!=1) {

if(ratio1_reduce%divisor==0 && ratio2_reduce%divisor==0 && ratio3_reduce%divisor==0){
                int ratio1_reduce_temp = ratio1_reduce/divisor;
                int ratio2_reduce_temp = ratio2_reduce/divisor;
                int ratio3_reduce_temp = ratio3_reduce/divisor;

ratio1_reduce = ratio1_reduce_temp;
                ratio2_reduce = ratio2_reduce_temp;
                ratio3_reduce = ratio3_reduce_temp;
                divisor--;
            }
            else divisor--;

}
            
            Console.WriteLine(ratio1+":"+ratio2+":"+ratio3+" = "+ratio1_reduce+":"+ratio2_reduce+":"+ratio3_reduce);
        }
        
        public static void checkAlgebra(){
            
            for (int x = -40; x<40; x++) {
                
                int a = 62*x-68;
                int b = 35;
                
                if (a%b==0){
                        
                    Console.WriteLine(x);
                }
            }
            
            
        }

public static void addLineBreak(int linesPerSection, int totalLines) {
         
            for (int i=0; i<=totalLines; i++) {
                
                if (i%linesPerSection==0) {
                    
                    Console.WriteLine("Break");
                    
                }
                
                else Console.WriteLine("No");
                
            
            }
        }
                 
        public static void circleX(double x, double radius) {
            
            Console.WriteLine("("+x+", "+Math.Round(Math.Sqrt(radius*radius-Math.Pow(x,2)),3)+")");
            
        }
        
        public static void circleY(double y, double radius) {
          
            Console.WriteLine("("+y+", "+Math.Round(Math.Sqrt(radius*radius-Math.Pow(y,2)),3)+")");
            
        }
        
        public static void angle(double x1, double y1, double x2, double y2, double x3, double y3) {
         
            double l12 = Math.Pow((x1-x2),2) +Math.Pow((y1-y2),2);
            double l13 = Math.Pow((x3-x1),2) +Math.Pow((y3-y1),2);
            double l23 = Math.Pow((x3-x2),2) +Math.Pow((y3-y2),2);
            
            double lhs = (l13-l12-l23)/(-2*Math.Sqrt(l12)*Math.Sqrt(l23));
            double angle2 = Math.Acos(lhs);
            //double angle2 = Math.Round(Math.Acos()*100,3);
            
            //Console.WriteLine(angle2 + " degrees C");
            Console.WriteLine(l12 + " " + l23 + " " + l13);
            Console.WriteLine(lhs);
                Console.WriteLine(angle2*360/(2*Math.PI)+" degrees");
        }
        
        
    }
    
    public static class Rand
    { 
        /// <summary> 
        /// Random number generator used to generate seeds, 
        /// which are then used to create new random number 
        /// generators on a per-thread basis. 
        /// </summary> 
        private static readonly Random globalRandom = new Random(); 
        private static readonly object globalLock = new object();

/// <summary> 
        /// Random number generator 
        /// </summary> 
        private static readonly ThreadLocal<Random> threadRandom = new ThreadLocal<Random>(NewRandom);

/// <summary> 
        /// Creates a new instance of Random. The seed is derived 
        /// from a global (static) instance of Random, rather 
        /// than time. 
        /// </summary> 
        public static Random NewRandom() 
        { 
            lock (globalLock) 
            { 
                return new Random(globalRandom.Next()); 
            } 
        }

/// <summary> 
        /// Returns an instance of Random which can be used freely 
        /// within the current thread. 
        /// </summary> 
        public static Random Instance { get { return threadRandom.Value; } }

/// <summary>See <see cref="Random.Next()" /></summary> 
        public static int Next() 
        { 
            return Instance.Next(); 
        }

/// <summary>See <see cref="Random.Next(int)" /></summary> 
        public static int Next(int maxValue) 
        { 
            return Instance.Next(maxValue); 
        }

/// <summary>See <see cref="Random.Next(int, int)" /></summary> 
        public static int Next(int minValue, int maxValue) 
        { 
            return Instance.Next(minValue, maxValue); 
        }

/// <summary>See <see cref="Random.NextDouble()" /></summary> 
        public static double NextDouble() 
        { 
            return Instance.NextDouble(); 
        }

/// <summary>See <see cref="Random.NextBytes(byte[])" /></summary> 
        public static void NextBytes(byte[] buffer) 
        { 
            Instance.NextBytes(buffer); 
        } 
        
        public static double NextD(double minValue, double maxValue) {
            
            return Instance.NextDouble()*(maxValue-minValue)+minValue;
        }
    } 
}

namespace ShuffleExtension {
    
    public static class ShuffleExtend {
        
        //private static readonly Random rnd = new Random();
        
        public static void Shuffle<T>(this IList<T> list) {
        
            int n = list.Count; 
       
            while (n > 1) {
            
                int k = (Rextester.Rand.Next(0, n) % n);
                n--;
                T value = list[k];
                list[k] = list[n];    
                list[n] = value;
        
            }
            
   
        }
    }
}

Show compiler warnings [ + ] Show input
Compilation time: 0,19 sec, absolute running time: 0,25 sec, cpu time: 0,11 sec, average memory usage: 18 Mb, average nr of threads: 4