Codeforces Round #340 (Div. 2) C. Watering Flowers

两种方法，一种n2，一种nlogn

#include <cstdio>#include <vector>typedef long long ll;using namespace std;ll pow(int a){    return a * (ll) a;}int main(){    int n, x1, x2, y1, y2;    scanf("%d%d%d%d%d", &n, &x1, &y1, &x2, &y2);    vector< pair<ll, ll> >vv(n);    for (int i = 0; i < n; i++)    {        int a, b;        scanf("%d%d", &a, &b);        vv[i].first = pow(a - x1) + pow(b - y1);        vv[i].second = pow(a - x2) + pow(b - y2);    }    vv.push_back({0, 0});    ll ans = 1e18;    for (int i = 0; i <= n; i++)    {        ll r1 = vv[i].first;        ll r2 = 0;        for (int j = 0; j <= n; j++)        {            if (vv[j].first > r1)            {                r2 = max(r2, vv[j].second);            }        }        ans = min(r1 + r2, ans);    }    printf("%I64d\n", ans);    return 0;}