Sum Of Digit Of A Number Using Recursion Through PHP Programming

In this post, I will discuss Sum Of Digit Of A Number Using Recursion Through PHP Programming.

Given a number, we need to find sum of its digits using recursion.

Examples:

Input : 12345
Output : 15

Input : 45632
Output :20

Now, the step by step process for a better understanding of how this algorithm works,

Lets, Take the example 12345

Step-1:

12345 % 10 which is equal-too 5 + and then send 12345/10 to next step.

Step-2:

1234 % 10 which is equal-too 4 + and then send 1234/10 to next step.

Step-3:

123 % 10 which is equal-too 3 + and then send 123/10 to next step.

Step-4:

12 % 10 which is equal-too 2 + and then send 12/10 to next step.

Step-5:

 1 % 10 which is equal-too 1 and then send 1/10 to next step.

Step-6:

 0 algorithm stops.

Here, following diagram will illustrate the process of recursion:

sum-of-digit-of-a-number-using-recursion — **Sum Of Digit Of Number Using Recursion**

<?php
// Recursive PHP program
// to find sum of digits
// of a number

// Function to check sum of
// digit using recursion
function sum_of_digit($n)
{
	if ($n == 0)
		return 0;
	return ($n % 10 +
			sum_of_digit($n / 10));
}

// Driven Code
$num = 12345;
$result = sum_of_digit($num);
echo("Sum of digits in " . $num . " is " . $result);

// This code is contributed by Ajit.
?>

Output: