Question

How to check if a number contains identical digits in C#

Answer 1

using System;
using System.Collections.Generic;
  
internal class NumberContainIdenticalDigits_CSharp
{
    static bool isNumberContainIdenticalDigits(int num) {
        string str = num.ToString();
        
        char[] arr = str.ToCharArray();
          
        var hset = new HashSet<char>(arr);
  
        return hset.Count == 1;
    }
      
    public static void Main(string[] args)
    {
        int num = 44444444;
     
        if (isNumberContainIdenticalDigits(num)) {
            Console.WriteLine("yes");
        } else {
            Console.WriteLine("no");
        }
    }
}

    
    
/*
run:
    
yes
    
*/

 

70+ SQL courses for beginners and professionals