啊啊，怎么写都是50分代码，求大佬纠正

feng_chenShy @ 2024-02-11 11:28:59

#include<bits/stdc++.h>  
using namespace std;  
int n;  
unsigned long long s=0;  
long long cf(int n)
{  
    long long a=1;  
    for(int i=n;i>=1;i--) 
        a*=i;
    return a;
}
int main()
{  
    cin>>n;  
    for(int i=1;i<=n;i++)
    {  
        s+=cf(i);  
    }  
    cout<<s<<endl;  
    return 0;  
}

by DFs_YYDS @ 2024-02-11 11:31:22

@18762057392spx 好像需要用高精

by feng_chenShy @ 2024-02-11 11:48:22

@DFs_YYDS
换成double后还是50分

by Limitless_lmw @ 2024-02-11 11:53:05

@18762057392spx 请自行查阅相关知识高精度，和什么 double 没关系

https://oi-wiki.org/math/bignum/

by wanderer___ @ 2024-02-11 12:30:20

@18762057392spx 要用高精加

by feng_chenShy @ 2024-02-11 12:31:53

知道了！谢谢各位大佬