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Check If A Given String Is Palindrome Or Not Using Loop

I will check whether the given string is a palindrome or not with 2 options using while and for loop.

It is a simple strategy to traverse the string in reverse using length property. Both options return True or False as their result.

In order to execute the code I’ve created a simple console application to print out the result.

Please find complete code below:

  1. Using While loop

This logic also takes care of the capitalization of the letters. Therefore, ‘Radar’ and ‘radar’ will give same result.

User input string: “Hello World!”

using System;

namespace PracticeConsole
{
   class Program
   {
      static void Main(string[] args)
      {
         Console.WriteLine("Please input the string and then hit enter:");
         string myString = Console.ReadLine();
         int min = 0;
         int max = myString.Length - 1;
         bool isPalindrome = false;
         while (true)
         {
            if (min > max)
            {
               isPalindrome = true;
            }
            char a = myString[min];
            char b = myString[max];
            if (char.ToLower(a) != char.ToLower(b))
            {
               isPalindrome = false;
            }
            min++;
            max--;
         }
         Console.WriteLine(isPalindrome);
         Console.ReadLine();
      }
   }
}

Result: False

 

2. Using For loop

This logic doesn’t takes capitalization of the letters into account. Therefore, ‘Radar’ and ‘radar’ will give different results.

User input string: “radar”

using System;

namespace PracticeConsole
{
   class Program
   {
      static void Main(string[] args)
      {
         Console.WriteLine("Please input the string and then hit enter:");
         string myString = Console.ReadLine();
         string reversedString= "";
         bool isPalindrome = false;
         for (int i = myString.Length - 1; i >= 0; i--)
         {
            reversedString += myString[i].ToString();
         }
         if (reversedString == myString)
         {
            isPalindrome = true;
            return isPalindrome;
         }
         else
         {
            isPalindrome = false;
            return isPalindrome;
         }
         Console.WriteLine(isPalindrome);
         Console.ReadLine();
      }
   }
}

Result: True

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