Reverse Number Program in C#

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Reverse a Number and a String in C# with Examples

In this article, I am going to discuss the How to Reverse a Number and a String in C# with Examples. Please read our previous article where we discussed the Palindrome Program in C# with some examples. This is one of the most frequently asked written interview questions in C#. As part of this article, we are going to discuss the following pointers.

1. How to Reverse a Given Number in C#?
2. How to Reverse a Given String in C#?

How to reverse a given number in C#?

In the following C# program, we take the input number from the console and then reverse that number.

using System;
namespace LogicalPrograms
{
    public class Program
    {
        static void Main(string[] args)
        {
            Console.Write("Enter a Number : ");
            int number = int.Parse(Console.ReadLine());
            int reminder, reverse = 0;

            while (number > 0)
            {
                //Get the remainder by dividing the number with 10  
                reminder = number % 10;

                //multiply the sum with 10 and then add the reminder
                reverse = (reverse * 10) + reminder;

                //Get the quotient by dividing the number with 10 
                number = number / 10;
            }

            Console.WriteLine($"The Reverse order is : {reverse}");
            Console.ReadKey();
        }
    }
}

Output:

How to reverse a string in C#?

In the following C# program, we take the string as an input from the console. Then we reverse the string using for loop.

using System;
namespace LogicalPrograms
{
    public class Program
    {
        static void Main(string[] args)
        {
            Console.Write("Enter a String : ");
            string name = Console.ReadLine();
            string reverse = string.Empty;

            for (int i = name.Length - 1; i >= 0; i--)
            {
                reverse += name[i];
            }

            Console.WriteLine($"The Reverse string is : {reverse}");
            Console.ReadKey();
        }
    }
}

Output:

Reverse a string Using Foreach loop in C#:

Let us see how to reverse a string using for each loop in C#.

using System;
namespace LogicalPrograms
{
    public class Program
    {
        static void Main(string[] args)
        {
            Console.Write("Enter a String : ");
            string name = Console.ReadLine();
            string reverse = string.Empty;
            foreach (char c in name)
            {
                reverse = c + reverse;
            }
            
            Console.WriteLine($"The Reverse string is : {reverse}");
            Console.ReadKey();
        }
    }
}

Output:

Reverse a string using Array.Reverse Method in C#:

In the following example, we take a string as an input from the console and then convert that string to a character array. Then we use the Array class Reverse method to reverse the elements of the character array. Once we reverse the elements of the character array, then we create a string from that character array.

using System;
namespace LogicalPrograms
{
    public class Program
    {
        static void Main(string[] args)
        {
            Console.Write("Enter a String : ");
            string name = Console.ReadLine();

            char[] nameArray = name.ToCharArray();
            Array.Reverse(nameArray);
            string reverse = new string(nameArray);
            
            Console.WriteLine($"The Reverse string is : {reverse}");
            Console.ReadKey();
        }
    }
}

Output:

In the next article, I am going to discuss the Armstrong Number Program in C# with some examples. Here, in this article, I try to explain the different ways to Reverse a Number and a String in C# with examples. I hope you enjoy this Reverse a Number and a String in C# article.