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**Sum of Digits Program in C# with Examples:**

In this article, I am going to discuss the **Sum of Digits Program in C#** with some examples. Please read our previous article where we discussed the **Factorial Program in C#** with many different ways. This is one of the frequently asked interview questions. As part of this article, we will discuss the following things.

**How to find the sum of digits of a given number using a loop?****How to find the sum of digits of a given number using recursion?****Using LINQ to find the sum of digits of a number in C#.**

**Finding the sum of digits of a given number using a loop in C#:**

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Let us first understand the algorithm to find the sum digits of a number.

**Algorithm: Sum of Digits Program in C#**

**Step1:** Get the number from the user

**Step2:** Get the modulus/remainder of that number by doing the modulus operation

**Step3:** Sum the remainder of the number

**Step4:** Divide the number by 10

**Step5:** Repeat step 2 while the number is greater than 0.

**Let us put the above steps into a program.**

using System; namespace LogicalPrograms { public class Program { static void Main(string[] args) { Console.Write("Enter the Number : "); int number = int.Parse(Console.ReadLine()); int sum = 0, reminder; while (number > 0) { reminder = number % 10; sum = sum + reminder; number = number / 10; } Console.WriteLine($"The Sum of Digits is : {sum}"); Console.ReadKey(); } } }

**Output:**

**Finding the sum of digits of a number using Recursion in C#:**

Let us understand how to find the sum of digits of a number using Recursion in C#. Please have a look at the following program.

using System; namespace LogicalPrograms { public class Program { static void Main(string[] args) { Console.Write("Enter the Number : "); int number = int.Parse(Console.ReadLine()); int sum = SumOfDigits(number); Console.WriteLine($"The Sum of Digits is : {sum}"); Console.ReadKey(); } static int SumOfDigits(int number) { if (number != 0) { return (number % 10 + SumOfDigits(number / 10)); } else { return 0; } } } }

**Output:**

**Using Linq to find the sum of digits of a number in C#:**

In the following program, first, we convert the integer into a string. As we know a string is an array of characters, so we use the Select operator to iterate over the array. For each character digit, first we parse it to a string and then we parse it to an int. Send the resulting enum to an int[] array. And then apply the Sum extension method on it to get the desired result.

using System; using System.Linq; namespace LogicalPrograms { public class Program { static void Main(string[] args) { Console.Write("Enter the Number : "); int number = int.Parse(Console.ReadLine()); int sum = number.ToString().Select(digit => int.Parse(digit.ToString())).ToArray().Sum(); Console.WriteLine($"The Sum of Digits is : {sum}"); Console.ReadKey(); } } }

**Output:**

In the next article, I am going to discuss **Decimal to Binary Conversion Program in C#** with some examples. Here, in this article, I try to explain the **Sum of Digits Program in C#** with many different ways. I hope you enjoy this article.