4973

Run ID	Author	Problem	Lang	Verdict	Time	Memory	Code Length	Submit Time
4973	盛梓恒_cat	[在线测评解答教程] 求和	C	Accepted	0 MS	192 KB	126	2023-01-13 14:02:18

#include<stdio.h> int main() { int n; while (scanf("%d", &n) != EOF) { printf("%d\n", n * (n + 1) / 2 ); } return 0; }