Find The First Repeated Character In A String

In this blog, we will study how we can find the first repeated character in a string.

Introduction

In this blog, we will study how we can find the first repeated character in a string.

Given below code snippet will help you to understand how we will find first repeated character in a string.

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

namespace CSharpAdvanncedProgramming
{
    public static class FirstRepeating
    {
        public static char FirstRepeatingChar(char[] chars)
        {
            HashSet<char> result = new HashSet<char>(); 
            for (int i = 0; i < chars.Length; i++)
            {
                char c = chars[i];
                if (result.Contains(c))
                {
                    return c;
                }
                else
                {
                    result.Add(c);
                }
            }
            return '\0';
        }
    }
}

Main Class Code 

using CSharpAdvanncedProgramming;
string Input = "Mudassar Ali";
Char[] chars = Input.ToCharArray();
char res = FirstRepeating.FirstRepeatingChar(chars);
Console.WriteLine("First Repeated Char In String Is :"+res);

Program Output