3380

Run ID	Author	Problem	Lang	Verdict	Time	Memory	Code Length	Submit Time
3380	盛梓恒_cat	[在线测评解答教程] 求和	C++	Wrong Answer	0 MS	236 KB	158	2023-01-06 21:07:38

#include<bits/stdc++.h> using namespace std; int main(){ int n; while(cin>>n){ if(n==1) cout<<1; else cout<<n*(n-1)/2; } }