HDU-2017 多校训练赛5-1006-Rikka with Graph

ACM模版

描述

题解

这个题看着很复杂，代码却是十分简单，直接看代码吧，不是特别难。几个判断就能搞定了……

代码

#include <iostream>using namespace std;typedef long long ll;ll n, m;int main(){    int T;    scanf("%d", &T);    while (T--)    {        scanf("%lld%lld", &n, &m);        if (m >= n - 1)        {            ll sum = n * (n - 1) / 2;            if (m > sum)            {                printf("%lld\n", sum * 2);            }            else            {                ll ans = (sum - m) * 2ll + m;                printf("%lld\n", ans * 2);            }        }        else        {            ll sum = n * (n - 1) / 2;            ll ans = m + m * (m - 1) + n * 1ll * (sum - m - m * (m - 1) / 2);            printf("%lld\n", ans * 2);        }    }    return 0;}