题解 | n的阶乘

#include <stdio.h>

double Factorial(int n);

int main() {
    int n;
    while(scanf("%d",&n)!=EOF){
        printf("%lld",(long long)Factorial(n));
    }
}

double Factorial(int n){
    if(n==1) return 1;
    return Factorial(n-1)*n;
}