結果

問題 No.3074 Divide Points Fairly
ユーザー Today03
提出日時 2025-03-28 23:28:48
言語 C++23
(gcc 13.3.0 + boost 1.87.0)
結果
RE  
実行時間 -
コード長 3,338 bytes
コンパイル時間 3,798 ms
コンパイル使用メモリ 302,148 KB
実行使用メモリ 31,200 KB
最終ジャッジ日時 2025-03-28 23:29:14
合計ジャッジ時間 25,028 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge2
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ファイルパターン 結果
sample RE * 3
other WA * 3 RE * 39
権限があれば一括ダウンロードができます

ソースコード

diff # 

#include <bits/stdc++.h>
#define ALL(x) (x).begin(), (x).end()
#define LB(v, x) (int)(lower_bound(ALL(v), x) - (v).begin())
#define UQ(v) sort(ALL(v)), (v).erase(unique(ALL(v)), (v).end())
#define IO ios::sync_with_stdio(false), cin.tie(nullptr);
#define chmax(a, b) (a) = (a) < (b) ? (b) : (a)
#define chmin(a, b) (a) = (a) < (b) ? (a) : (b)
using namespace std;
using ll = long long;
const int INF = 1e9 + 10;
const ll INFL = 4e18;

int main() {
    auto sign = [&](ll x) {
        if (x < 0) return -1;
        if (x == 0) return 0;
        return 1;
    };
    auto solve = [&](ll cx, vector<pair<ll, ll>> xy) -> tuple<ll, ll, ll> {
        int n = ssize(xy) / 2;
        vector<tuple<double, ll, ll>> arg;
        for (auto [x, y] : xy) {
            arg.emplace_back(atan2(y, x - cx), x, y);
            arg.emplace_back(atan2(y, x - cx) + numbers::pi + 2, x, y);
        }
        sort(ALL(arg));
        for (int i = 0; i < 2 * n; i++) {
            int j = LB(arg, make_tuple(get<0>(arg[i]) + numbers::pi, -INFL, -INFL));
            if (j - i == n) {
                auto [t, x, y] = arg[i];
                ll bunbo = x - cx, bunsi = -y;
                if (abs(bunbo) > abs(bunsi)) {
                    bunbo = sign(bunbo) * (bunbo + 1);
                    bunsi = sign(bunsi) * (bunsi + 1);
                } else if (abs(bunbo) < abs(bunsi)) {
                    bunbo = sign(bunbo) * (bunbo - 1);
                    bunsi = sign(bunsi) * (bunsi - 1);
                } else {
                    bunbo *= 10, bunsi *= 10;
                    bunbo += 2, bunsi += 1;
                }
                return make_tuple(bunsi, -bunbo, bunsi * cx);
            }
        }
        return make_tuple(0, 0, 0);
    };

    int N;
    cin >> N;
    vector<pair<ll, ll>> XY(2 * N);
    for (auto& [x, y] : XY) cin >> x >> y, x *= 2, y *= 2;

    auto check = [&](ll a, ll b, ll c) {
        int n = 0;
        if (b == 0) {
            // ax=c
            for (auto [x, y] : XY) {
                if (a * x == -c) return false;
                if (a * x > -c) n++;
            }
            return n == N / 2;
        }
        for (auto [x, y] : XY) {
            if (a * x + b * y + c == 0) return false;
            if (b * y > -a * x - c) n++;
        }
        return n == N / 2;
    };

    map<int, int> cnt;
    for (auto [x, y] : XY) cnt[x]++;

    ll sum = 0;
    for (int i = -5e5; i <= 5e5; i += 2) {
        sum += cnt[i];
        if (sum > N) {
            {
                auto [a, b, c] = solve(i + 1, XY);
                if (a != 0 || b != 0 || c != 0) {
                    assert(check(a, b, c));
                    a *= 2, b *= 2;
                    ll g = gcd(abs(a), gcd(abs(b), abs(c)));
                    a /= g, b /= g, c /= g;
                    cout << a << ' ' << b << ' ' << c << endl;
                    return 0;
                }
            }
            {
                auto [a, b, c] = solve(i - 1, XY);
                if (a != 0 || b != 0 || c != 0) {
                    assert(check(a, b, c));
                    a *= 2, b *= 2;
                    ll g = gcd(abs(a), gcd(abs(b), abs(c)));
                    a /= g, b /= g, c /= g;
                    cout << a << ' ' << b << ' ' << c << endl;
                    return 0;
                }
            }
        }
    }
}
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