Submission #703491

#	Time	Username	Problem	Language	Result	Execution time	Memory
703491		Cyanmond	Magic Tree (CEOI19_magictree)	C++17	100 / 100	188 ms	33964 KiB

magictree

#include <bits/stdc++.h>

using i64 = long long;
struct Vertice {
    bool exFruit;
    int day;
    i64 weight;
};

int main() {
    int N, M, K;
    std::cin >> N >> M >> K;
    std::vector<int> P(N);
    std::vector<std::vector<int>> tree(N);
    for (int i = 1; i < N; ++i) {
        std::cin >> P[i];
        --P[i];
        tree[P[i]].push_back(i);
    }
    std::vector<int> U(M), D(M);
    std::vector<i64> W(M);
    std::vector<Vertice> vData(N);
    for (int i = 0; i < M; ++i) {
        std::cin >> U[i] >> D[i] >> W[i];
        --U[i];
    }
    {
        // press
        auto cD = D;
        std::sort(cD.begin(), cD.end());
        cD.erase(std::unique(cD.begin(), cD.end()), cD.end());
        for (auto &e : D) {
            e = (int)(std::lower_bound(cD.begin(), cD.end(), e) - cD.begin());
        }
        K = (int)cD.size();
    }
    for (int i = 0; i < M; ++i) {
        vData[U[i]] = {true, D[i], W[i]};
    }

    auto merge = [&] (std::map<int, i64> &a, std::map<int, i64> &b) {
        if (a.size() < b.size()) {
            std::swap(a, b);
        }
        for (const auto &[k, v] : b) {
            a[k] += v;
        }
    };

    auto dfs = [&](auto &&self, const int v) -> std::map<int, i64> {
        // calc DP
        std::map<int, i64> ret;
        for (const int t : tree[v]) {
            auto res = self(self, t);
            merge(ret, res);
        }
        // cut
        if (vData[v].exFruit) {
            ret[vData[v].day] += vData[v].weight;
            auto itr = ret.upper_bound(vData[v].day);
            i64 sum = vData[v].weight;
            while (itr != ret.end() and sum != 0) {
                if (itr->second <= sum) {
                    sum -= itr->second;
                    itr = ret.erase(itr);
                } else {
                    itr->second -= sum;
                    sum = 0;
                }
            }
        }
        return ret;
    };
    const auto res = dfs(dfs, 0);
    i64 answer = 0;
    for (const auto &[k, v] : res) {
        answer += v;
    }
    std::cout << answer << std::endl;
}

• Subtask 1: 6 / 6
• Subtask 2: 3 / 3
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12
• Subtask 5: 16 / 16
• Subtask 6: 13 / 13
• Subtask 7: 22 / 22
• Subtask 8: 17 / 17