Submission #201305

#	Time	Username	Problem	Language	Result	Execution time	Memory
201305		jun6873	Fireworks (APIO16_fireworks)	C++11	100 / 100	253 ms	89720 KiB

fireworks

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

using lint = long long;
using pint = pair<int, int>;
#define x first
#define y second

const int maxn = 300004;

int N, M;
vector<pint> g[maxn];

struct func {
    priority_queue<lint> neg;
    priority_queue<lint, vector<lint>, greater<lint> > pos;
    lint mn = 0;
    void balance() {
        while (neg.top() > pos.top()) {
            lint x = neg.top(), y = pos.top();
            neg.pop(); pos.pop();
            pos.push(x); neg.push(y);
            mn += x - y;
        }
    }
    void add(lint a, lint b, lint c) {
        neg.push(a);
        pos.push(b);
        mn += c;
        balance();
    }
    void process(lint x) {
        lint b = neg.top() + x, c = pos.top() + x;
        while (!pos.empty()) pos.pop();
        neg.pop();
        neg.push(b);
        pos.push(c);
    }
} *b[maxn];

void dfs(int x) {
    func *f = new func();
    for (pint i : g[x]) if (!g[i.x].empty()) {
        dfs(i.x);
        b[i.x]->process(i.y);
        if (f->neg.size() < b[i.x]->neg.size()) f = b[i.x];
    }
    b[x] = f;

    for (pint i : g[x]) if (f != b[i.x]) {
        if (!g[i.x].empty()) {
            func *g = b[i.x];
            while (!g->neg.empty()) f->neg.push(g->neg.top()), g->neg.pop();
            while (!g->pos.empty()) f->pos.push(g->pos.top()), g->pos.pop();
            f->mn += g->mn;
            f->balance();
        } else f->add(i.y, i.y, 0);
    }

}

int main() {
    ios::sync_with_stdio(0); cin.tie(0);

    cin >> N >> M;

    for (int i=2; i<=N+M; i++) {
        int x, y;
        cin >> x >> y;
        g[x].emplace_back(i, y);
    }

    dfs(1);

    cout << b[1]->mn << '\n';
}

• Subtask 1: 7 / 7
• Subtask 2: 19 / 19
• Subtask 3: 29 / 29
• Subtask 4: 45 / 45