c# string abbreviation, C#

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/*
 * C# Program to Display the Abbreviation of a Text
 */
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
class abbreviation
{
    string str;
    public void readdata()
    {
        Console.WriteLine("Enter a String :");
        str=Console.In.ReadLine();
    }
    public void abbre()
    {
        char[] c, result;
        int j = 0;
        c = new char[str.Length];
        result = new char[str.Length];
        c = str.ToCharArray();
        result[j++] = (char)((int)c[0] ^ 32);
        result[j++] = '.';
        for (int i = 0; i < str.Length - 1; i++)
        {
            if (c[i] == ' ' || c[i] == '\t' || c[i] == '\n')
            {
                int k = (int)c[i + 1] ^ 32;
                result[j++] = (char)k;
                result[j++] = '.';
            }
        }
            Console.Write("The Abbreviation for {0} is ", str);
            Console.WriteLine(result);
            Console.ReadLine();
class initials { 
      
    static void printInitials(String name) 
    { 
        if (name.Length == 0) 
            return; 
  
        // Since touuper() returns int, 
        // we do typecasting 
        Console.Write(Char.ToUpper(name[0])); 
  
        // Traverse rest of the string and  
        // print the characters after spaces. 
        for (int i = 1; i < name.Length - 1; i++) 
            if (name[i] == ' ') 
                Console.Write(" " + Char.ToUpper(name[i + 1])); 
    } 
 
    }
        public static void Main()
        {
            abbreviation obj=new abbreviation();
            obj.readdata();
            obj.abbre();
{
 String name = "prabhat kumar singh"; 
        printInitials(name); }
        }
}

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