77710

Run ID	Author	Problem	Lang	Verdict	Time	Memory	Code Length	Submit Time
77710	sh25_zhangjiajia	分苹果	C++	Accepted	0 MS	244 KB	131	2025-12-26 14:42:15

#include <bits/stdc++.h> using namespace std; int main() { int n; cin>>n; cout<<n * (n + 1) / 2; return 0; }