[Programming] Question 6: Calculate the factorial of a number in C?

Learn how to write a C program to calculate the factorial of a number. This guide explains how to implement iterative methods for computing the factorial, including detailed examples and explanations. Ideal for beginners who want to understand fundamental concepts in C programming and factorial computation.

#include <stdio.h>

int main() {
	int n, i;
	unsigned long long factorial = 1;

	printf("Enter a positive integer: ");
	scanf("%d", &n);

	for (i = 1; i <= n; ++i) {
		factorial *= i;
	}

	printf("Factorial of %d = %llu\n", n, factorial);

	return 0;
} 

Explanation: 

Inside the main() function:

- An integer variable n is declared to store the input number.

- An unsigned long long variable factorial is initialized to 1 to store the factorial value.

- The user is prompted to enter a positive integer.

- A for loop is used to iterate from 1 to the entered number.

- Within the loop, each number is multiplied to the factorial variable.

- Finally, the factorial of the entered number is printed to the console.