Submission #520018

#	Time	Username	Problem	Language	Result	Execution time	Memory
520018		KoD	Putovanje (COCI20_putovanje)	C++17	110 / 110	110 ms	22988 KiB

putovanje

#include <bits/stdc++.h>

using std::vector;
using std::array;
using std::pair;
using std::tuple;

template <class F> struct RecLambda : private F {
    explicit RecLambda(F&& f) : F(std::forward<F>(f)) {}
    template <class... Args> decltype(auto) operator()(Args&&... args) const {
        return F::operator()(*this, std::forward<Args>(args)...);
    }
};

int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int N;
    std::cin >> N;
    vector<int> to(2 * N - 2), once(2 * N - 2), mult(2 * N - 2);
    vector<vector<int>> graph(N);
    for (int i = 0; i < N - 1; ++i) {
        int a, b, c, d;
        std::cin >> a >> b >> c >> d;
        a -= 1, b -= 1;
        to[2 * i] = b;
        to[2 * i + 1] = a;
        once[2 * i] = once[2 * i + 1] = c;
        mult[2 * i] = mult[2 * i + 1] = d;
        graph[a].push_back(2 * i);
        graph[b].push_back(2 * i + 1);
    }
    vector<int> depth(N);
    array<vector<int>, 20> parent;
    parent[0] = vector(N, 0);
    RecLambda([&](auto&& dfs, const int u, const int p) -> void {
        parent[0][u] = p;
        for (const int e : graph[u]) {
            if (to[e] != p) {
                depth[to[e]] = depth[u] + 1;
                dfs(to[e], u);
            }
        }
    })(0, 0);
    for (int k = 0; k < 19; ++k) {
        parent[k + 1] = vector(N, 0);
        for (int i = 0; i < N; ++i) {
            parent[k + 1][i] = parent[k][parent[k][i]];
        }
    }
    const auto lca = [&](int u, int v) {
        if (depth[u] < depth[v]) {
            std::swap(u, v);
        }
        for (int dif = depth[u] - depth[v], k = 0; k < 20; ++k) {
            if (dif >> k & 1) {
                u = parent[k][u];
            }
        }
        if (u == v) {
            return u;
        }
        for (int k = 19; k >= 0; --k) {
            if (parent[k][u] != parent[k][v]) {
                u = parent[k][u];
                v = parent[k][v];
            }
        }
        return parent[0][u];
    };
    vector<int> coeff(N);
    for (int i = 1; i < N; ++i) {
        const int j = lca(i - 1, i);
        coeff[i - 1] += 1;
        coeff[i] += 1;
        coeff[j] -= 2;
    }
    long long ans = 0;
    RecLambda([&](auto&& dfs, const int u, const int p) -> void {
        for (const int e : graph[u]) {
            if (to[e] != p) {
                dfs(to[e], u);
                coeff[u] += coeff[to[e]];
                ans += std::min((long long)coeff[to[e]] * once[e], (long long)mult[e]);
            }
        }
    })(0, 0);
    std::cout << ans << '\n';
    return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 25 / 25
• Subtask 3: 65 / 65