#include<stdio.h>
#include<stdlib.h>

int fact(int a)
{
    int i,ret;
    ret=1;
    for(i=1;i<=a;i++)
    	ret=ret*i;
    
    return ret;
}


int main()
{
    int n;
    printf("Enter number: ");
    scanf("%d",&n);
    
    printf("%d",fact(n));
    
    printf("\n");
    system("pause");
}