Submission #1250278

#	Time	Username	Problem	Language	Result	Execution time	Memory
1250278		sus	Fountain (eJOI20_fountain)	C++20	100 / 100	368 ms	57328 KiB

fountain

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

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n, q;
    cin >> n >> q;
    vector<pair<int, int>> containers(n + 1);
    containers[0] = {1e9, 1e9};
    for (int i = 1; i <= n; i++)
    {
        cin >> containers[i].first;
        cin >> containers[i].second;
    }
    vector<pair<int, int>> questions(q);
    for (int i = 0; i < q; i++)
    {
        cin >> questions[i].first;
        cin >> questions[i].second;
    }
    vector<pair<int, int>> containers_overflow;
    int max_pow = 30;
    vector<vector<pair<int, long long>>> jump(n + 1, vector<pair<int, long long>>(max_pow + 1));
    containers_overflow.push_back({0, 1e9});
    int current_container;
    for (int i = n; i >= 1; i--)
    {
        while (containers[i].first >= containers_overflow.back().second)
        {
            containers_overflow.pop_back();
        }
        current_container = containers_overflow.back().first;
        jump[i][0] = {current_container, containers[current_container].second};
        containers_overflow.push_back({i, containers[i].first});
    }
    int where, capacity;
    for (int l = 1; l <= max_pow; l++)
    {
        for (int v = n; v >= 1; v--)
        {
            where = jump[jump[v][l - 1].first][l - 1].first;
            if (where == 0)
            {
                capacity = 1e9;
            }
            else
            {
                capacity = jump[v][l - 1].second + jump[jump[v][l - 1].first][l - 1].second;
            }
            jump[v][l] = {where, capacity};
        }
    }
    int wasser;
    int start;
    for (int i = 0; i < q; i++)
    {
        start = questions[i].first;
        wasser = questions[i].second;
        wasser = max(wasser - containers[start].second, 0);
        for (int p = max_pow; p >= 0; p--)
        {
            if (jump[start][p].second <= wasser)
            {
                wasser -= jump[start][p].second;
                start = jump[start][p].first;
            }
        }
        if (wasser > 0)
        {
            start = jump[start][0].first;
        }
        cout << start << endl;
    }
}

• Subtask 1: 30 / 30
• Subtask 2: 30 / 30
• Subtask 3: 40 / 40