求大佬

#include<iostream>
using namespace std;
unsigned long long jie(int a){
	unsigned long long b=1;
	for(long long i=1;i<=a;i++){
		b*=i;
	}
	return b;
}
int main(){
    long long n;
    cin>>n;
    unsigned long long h=0;
    for(long long i=1;i<=n;i++){
    	unsigned long long m=jie(i);
    	h+=m;
	}
	cout<<h;
	return 0;
}