44129

Run ID	Author	Problem	Lang	Verdict	Time	Memory	Code Length	Submit Time
44129	承诺	求1+2+3+...	C++	Accepted	0 MS	244 KB	106	2024-03-29 14:56:20

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