#include <stdio.h>
long fakt( long );
int main()
{
long i, n, sum = 0;
printf("Input N: ");
scanf("%d", &n);
for ( i = 1 ; i <= n ; i++ )
sum += fakt(i);
printf ("Summa = %ld\n", sum );
return 0;
}
long fakt( long a )
{
if ( a <= 1 )
return 1;
else
return a * fakt(a-1);
}