#include<stdio.h>
int factorial (int);
main( )
{
    int a, fact ;
    printf ( "\nEnter any number : " ) ;
    scanf ( "%d", &a ) ;
    fact = factorial ( a ) ;
    printf ( "Factorial value = %d \n", fact ) ;
    system("pause");
}
int factorial ( int x )
{
    int f = 1, i ;
    for ( i = x ; i >= 1 ; i-- )
        f = f * i ;
    return ( f ) ;
}