Submission #1279646

#	Time	Username	Problem	Language	Result	Execution time	Memory
1279646		not_amir	Magic Tree (CEOI19_magictree)	C++20	100 / 100	309 ms	272216 KiB

magictree

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

struct vertex {
    vertex *vl = nullptr, *vr = nullptr;
    ll mxv = 0, add = 0;

    void extend(vertex *&v) {
        if (v == nullptr)
            v = new vertex();
    }

    void update(int tl, int tr, int l, int r, ll val, ll sum = 0) {
        if (l >= r)
            return;
        sum += add;
        if (l == tl && r == tr)
            mxv = max(mxv, val - sum);
        else {
            int tm = (tl + tr) / 2;
            extend(vl), vl->update(tl, tm, l, min(r, tm), val, sum);
            extend(vr), vr->update(tm, tr, max(l, tm), r, val, sum);
        }
    }

    ll get_max(int tl, int tr, int x, ll sum = 0) {
        sum += add;
        if (tl + 1 == tr)
            return sum + mxv;
        int tm = (tl + tr) / 2;
        return max(sum + mxv, x < tm ? vl ? vl->get_max(tl, tm, x, sum) : 0 : vr ? vr->get_max(tm, tr, x, sum) : 0);
    }
};

vertex* merge(int tl, int tr, vertex *v1, vertex *v2, ll m1 = 0, ll m2 = 0, ll s1 = 0, ll s2 = 0) {
    if (v1 == nullptr && v2 == nullptr)
        return nullptr;
    if (v1 == nullptr) {
        v2->add += m1 + s2;
        return v2;
    }
    if (v2 == nullptr) {
        v1->add += m2 + s1;
        return v1;
    }
    vertex *v = new vertex();
    s1 += v1->add, s2 += v2->add;
    m1 = max(m1, s1 + v1->mxv), m2 = max(m2, s2 + v2->mxv);
    v->mxv = m1 + m2;
    if (tl + 1 == tr)
        return v;
    int tm = (tl + tr) / 2;
    v->vl = merge(tl, tm, v1->vl, v2->vl, m1, m2, s1, s2);
    v->vr = merge(tm, tr, v1->vr, v2->vr, m1, m2, s1, s2);
    return v;
}

typedef pair<int, int> pii;

vector<vector<int>> G;
vector<pii> fruits;

int k;

vertex *dfs(int v) {
    vertex *ret = new vertex();
    for (int u : G[v])
        ret = merge(0, k, ret, dfs(u));
    auto [d, w] = fruits[v];
    if (d) {
        ll mxv = ret->get_max(0, k, d);
        ret->update(0, k, d, k, mxv + w);
    }
    return ret;
}
int main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int n, m;
    cin >> n >> m >> k;
    k++;
    G.resize(n + 1);
    fruits.resize(n + 1);
    for (int i = 2; i <= n; i++) {
        int p;
        cin >> p;
        G[p].push_back(i);
    }
    for (int i = 0; i < m; i++) {
        int v, d, w;
        cin >> v >> d >> w;
        fruits[v] = {d, w};
    }
    cout << dfs(1)->get_max(0, k, k - 1);
}

• 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