#include
#define N 3
double fun(int x)
{
int i;
double y=1;
for(i=1;i<=x;i++)
y=y*i;
return y;
}
int main()
{
printf("%lfn",fun(N));
}

#include
#define N 3
double fun(int x)
{
int i;
double y=1;
for(i=1;i<=x;i++)
y=y*i;
return y;
}
int main()
{
printf("%lfn",fun(N));
}