**Factorial without Recursion**

#include <stdio.h>

int main()

{

int n, i;

unsigned long long factorial = 1;

printf("Enter an integer: ");

scanf("%d",&n);

// show error if the user enters a negative integer

if (n < 0)

printf("Error! Factorial of a negative number doesn’t exist.");

else

{

for(i=1; i<=n; ++i)

{

factorial *= i; // factorial = factorial*i;

}

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

}

return 0;

}

**Factorial of Number in C-Programming using Recursion**

#include <stdio.h>

long int multiplyNumbers(int n);

int main()

{

int n;

printf("Enter a positive integer: ");

scanf("%d", &n);

printf("Factorial of %d = %ld", n, multiplyNumbers(n));

return 0;

}

long int multiplyNumbers(int n)

{

if (n >= 1)

return n*multiplyNumbers(n-1);

else

return 1;

}