Sort A List of Ages of Students (Solution: Stack / O(N^3) Complexity), C#

Language: Layout:

//Problem:  Sort a list of ages of all the students
//Solution: Use a stack to arrange the order of the ages

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

namespace Rextester
{
    public class Program
    {
        public class Student
        {
            public string Name { get; set; }
            public int Age {get; set;}
            
        }
                    
        public static List<Student> StudentList;    
        
        
        public static void Main(string[] args)
        {
          
            //Prepare the list of students
            LoadStudents();
                   
           
            //Create a stack
            int[] sortedAgeStack = new int[StudentList.Count()];
            int stackTop = -1;
            
            foreach ( Student s in StudentList)
            {
                int currentValue = s.Age;
                //If stack is empty, just insert the age
                if(stackTop == -1)
                {
                      stackTop++;
                      sortedAgeStack[stackTop]=currentValue;
                }
                else
                {
                    int insertIndex = -1;
                    //find the location to insert by going through all the values in the stack
                    for(int i=0;i<=stackTop;i++)
                    {
                        
                        if(i==0 && currentValue <= sortedAgeStack[i])
                        {
                            insertIndex = i;
                        }
                        else if(currentValue <= sortedAgeStack[i] && currentValue >= sortedAgeStack[i-1])
                        {
                            insertIndex = i;
                        }
                    }
                    if(insertIndex != -1)
                    {
                        //move the elements first
                        for(int r=stackTop;r>=insertIndex;r--)
                        {
                            sortedAgeStack[r+1] = sortedAgeStack[r];
                        }
                        //insert on insertIndex
                        stackTop++;
                        sortedAgeStack[insertIndex]=currentValue;
                    }
                    else
                    {
                        //just insert after the last element
                        stackTop++;
                        sortedAgeStack[stackTop] = currentValue;
                    }
                    
                }
            }
            
            //Print the sorted list of ages
            PrintResult(sortedAgeStack);
                
            
        } 
        
        public static void PrintResult(int[] output)
        {
            foreach(int i in output)
                Console.WriteLine(i);
        }
        
        public static void LoadStudents()
        {
                          
            Student s = new Student(){ Name = "Ivy", Age = 33};
            Student s1 = new Student(){ Name = "Ryan", Age = 34};
            Student s2 = new Student(){ Name = "Ron", Age = 23};
            Student s3 = new Student(){ Name = "Melvin", Age = 2};
            Student s4 = new Student(){ Name = "Sara", Age = 33};
            Student s5 = new Student(){ Name = "Mars", Age = 43};
            Student s6 = new Student(){ Name = "Pluto", Age = 50};
            Student s7 = new Student(){ Name = "Neptune", Age = 6};
            Student s8 = new Student(){ Name = "Nero", Age = 5};
            Student s9 = new Student(){ Name = "Augustus", Age = 34};
           
            StudentList = new List<Student>();
            StudentList.Add(s);
            StudentList.Add(s1);
            StudentList.Add(s2);
            StudentList.Add(s3);
            StudentList.Add(s4);
            StudentList.Add(s5);
            StudentList.Add(s6);
            StudentList.Add(s7);
            StudentList.Add(s8);
            StudentList.Add(s9);
        }
        
        
    }
}

Show compiler warnings [ + ] Show input
Compilation time: 0,16 sec, absolute running time: 0,09 sec, cpu time: 0,06 sec, average memory usage: 14 Mb, average nr of threads: 3