Programming Example
C Program to Find Sum of Digits of a Number using Recursion
C Program to Find Sum of Digits of a Number using Recursion
/*
* C Program to find Sum of Digits of a Number using Recursion
* atnyla.com
*/
#include <stdio.h>
int sum (int a);
int main()
{
int num, result;
printf("Enter the number: ");
scanf("%d", &num);
result = sum(num);
printf("Sum of digits in %d is %d\n", num, result);
return 0;
}
int sum (int num)
{
if (num != 0)
{
return (num % 10 + sum (num / 10));
}
else
{
return 0;
}
} Enter the number: 123
Sum of digits in 123 is 6
In this C program, we are reading the integer number using the ‘num’ variable. The function sum() is used to find sum of digits of a number using recursion.
In function sum() check the value of ‘num’ variable is not equal to 0. If the condition is true execute the statement. Divide the value of ‘num’ variable by 10 integer value. Add the resulted value along with the modulus of the value of ‘num’ variable. Print the sum of digits of a number using recursion.
First read the algorithm, then study the program code line by line. After that, compare the code with the output and finally go through the explanation. This approach helps learners understand both the logic and the implementation properly.
After understanding this example, try to rewrite the same program without looking at the code. Then change some values or logic and run it again. This helps improve confidence and keeps learners engaged on the page for longer.