Submission #155871

#	Time	Username	Problem	Language	Result	Execution time	Memory
155871		Alexa2001	Fireworks (APIO16_fireworks)	C++17	100 / 100	308 ms	52840 KiB

fireworks

#include <bits/stdc++.h>

using namespace std;

const int Nmax = 3e5 + 5;
typedef long long ll;


ll A[Nmax], B[Nmax];
int up[Nmax], w[Nmax];
priority_queue<ll> heap[Nmax];
vector<int> edge[Nmax];

int n, m, N;

void combine(int node, int son)
{
    A[node] += A[son]; B[node] += B[son];

    while(heap[son].size())
    {
        heap[node].push(heap[son].top());
        heap[son].pop();
    }
}

void merge_sons(int node)
{
    int xson = 0;

    for(auto son : edge[node])
    {
        if(w[son] > w[xson]) xson = son;
        w[node] += w[son];
    }

    swap(heap[node], heap[xson]);
    A[node] = A[xson]; B[node] = B[xson];

    for(auto son : edge[node])
        if(son != xson)
            combine(node, son);
}

int main()
{
  //  freopen("input", "r", stdin);
    cin.sync_with_stdio(false); cin.tie(0);

    cin >> n >> m;
    N = n + m;

    int i, node;
    for(i=2; i<=N; ++i)
    {
        int parent;
        cin >> parent >> up[i];
        edge[parent].push_back(i);
    }

    for(node = N; node; --node)
    {
        w[node] = 1;

        if(edge[node].empty())
        {
            heap[node].push(up[node]);
            heap[node].push(up[node]);
            A[node] = 1; B[node] = -up[node];

            continue;
        }

        merge_sons(node);

        while(A[node] > 1)
        {
            ll last_change = heap[node].top();
            heap[node].pop();

            A[node]--; B[node] += last_change;
        }

        ll change0, change1;
        change1 = heap[node].top(); heap[node].pop();
        change0 = heap[node].top(); heap[node].pop();

        heap[node].push(change1 + up[node]);
        heap[node].push(change0 + up[node]);

        B[node] -= up[node];
    }

    cout << A[1] * heap[1].top() + B[1] << '\n';

    return 0;
}

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