C Program to calculate factorial using recursion

In this tutorial, we will learn to write the program to find the factorial of numbers using the C programming language. Here we are going to follow a recursive approach.

What is Factorial of a number?

Factorial of a whole number ‘n’ is the product of that number ‘n’ with its every whole number in descending order till 1.

For example

Factorial of 5 is 5*4*3*2*1 = 120

And factorial of 5 can be written as 5!.

Factorial Program in C using Recursion

#include<stdio.h>
long long fact(int num) {
  if (num == 0)
    return 1;
  else
    return (num * fact(num - 1));
}
int main() {
  int i, num, factorial = 1;
  printf("Enter a whole number to find Factorial = ");
  scanf("%d", & num);
  printf("Factorial of %d is: %llu", num, fact(num));
  return 0;
}

Output

Factorial Program in C using Recursion