How to check repeated letters in a string c#

Question

I am creating a program that checks repeated letters in a string.

For Example:

wooooooooooow
happpppppppy

This is my

Answer 1

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Delegate
{
    class Program
    {
       public int repeatcount(string str,char ch)
        {

            var count = 0;
            for (int i = 0; i<str.Length; i++)
            {
                if (ch == str[i])
                {
                    count++;
                }

            }

            return count;
        }
        static void Main(string[] args)
        {
            Console.WriteLine("Enter a string");
            string str = Console.ReadLine();
            Console.WriteLine("Enter to know the reperted char");
            char ch = Convert.ToChar(Console.ReadLine());
            Program obj = new Program();
            int p=obj.repeatcount(str, ch);
            Console.WriteLine(p);


            Console.ReadLine();

        }
    }



}

Answer 2

You can change your loop condition to have the -1 (as others have already pointed out), or you can do it the cool kid way.

var text = "wooooooooooow happpppppppy";
var repeats = text.Zip(text.Skip(1), (a, b) => a == b).Count(x => x);

Answer 3

using System;

namespace temp1
{
    class Program
    {
        static string str = "proffession";
        static int n = str.Length;
        static string dupstr = "";
        static int cnt = 0;
        static void Main()
        {
            RepeatedCharsString(); 
        }

        public static void RepeatedCharsString()
        {
            for (int i = 0; i < n ; i++)
            {
                for(int j = i + 1; j <= n-1; j++)
                {
                    if (str[i] == str[j])
                    {
                        dupstr = dupstr + str[i];
                        cnt = cnt + 1;
                    }
                }                
            }
            Console.WriteLine("Repeated chars are: " + dupstr);
            Console.WriteLine("No of repeated chars are: " + cnt);
        }
    }
}

Answer 4

 public int RepeatedLetters(string word)
        {
            var count = 0;
            for (var i = 0; i < word.Count()-1; i++)
            {
                if (word[i] == word[i+1])
                {
                    count++;
                }
            }
            return count;
        }