#include<stdio.h>

int factorial(int n);

int x;   /* Global variable */

void main()
{
  int n, f;

  printf("\n Enter n: ");
  scanf("%d", &n);

  f=factorial(n);

  printf("\n %d!=%d\n", n, f );

  printf("\n n  is now %d\n", n );

}


int factorial(int n)
{
  int f=1, i;

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

  
  return f;

}