oj.uz

Submission #802999

# Submission time Handle Problem Language Result Execution time Memory
802999 2023-08-02T17:37:34 Z andreiomd Fountain (eJOI20_fountain) C++11
100 / 100
 227 ms 14912 KB 
#include <iostream>
#include <stack>

using namespace std;
using PII = pair<int, int>;

static constexpr int NMAX = (int)(1e5 + 1), LOGMAX = 17;

int Log2[NMAX];

int N, Q;
int D[NMAX], C[NMAX];

PII Next[LOGMAX][NMAX];

static inline void Read()
{
    ios_base ::sync_with_stdio(false);
    cin.tie(nullptr);

    cin >> N >> Q;
    for (int i = 1; i <= N; ++i)
    {
        cin >> D[i] >> C[i], Next[0][i] = {0, 0};

        if (i >= 2)
            Log2[i] = 1 + Log2[(i >> 1)];
    }

    return;
}

static inline void Get_level_0()
{
    stack<int> S;

    for (int i = 1; i <= N; ++i)
    {
        while (!S.empty() && D[i] > D[S.top()])
            Next[0][S.top()].first = i, Next[0][S.top()].second += C[i], S.pop();

        S.push(i);
    }

    return;
}

static inline void Precompute()
{
    for (int i = 1; i <= Log2[N]; ++i)
        for (int j = 1; j <= N; ++j)
            if (Next[i - 1][j].first)
                if (Next[i - 1][Next[i - 1][j].first].first)
                    Next[i][j] = {Next[i - 1][Next[i - 1][j].first].first, Next[i - 1][j].second + Next[i - 1][Next[i - 1][j].first].second};

    return;
}

static inline void Test_Case()
{
    int node = 0, target = 0;
    cin >> node >> target;

    if (C[node] >= target)
    {
        cout << node << '\n';
        return;
    }

    if (!Next[0][node].first)
    {
        cout << 0 << '\n';
        return;
    }

    target -= C[node];

    for (int i = Log2[N - node + 1]; i >= 0; --i)
        if (Next[i][node].first)
            if (target - Next[i][node].second >= 0)
                target -= Next[i][node].second, node = Next[i][node].first;

    if (target == 0)
        cout << node;
    else
        cout << Next[0][node].first;

    cout << '\n';

    return;
}

static inline void Solve()
{
    for (int q = 1; q <= Q; ++q)
        Test_Case();

    return;
}

int main()
{
    Read();

    Get_level_0();

    Precompute();

    Solve();

    return 0;
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 102 ms 13860 KB Output is correct
2 Correct 101 ms 12796 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 102 ms 13860 KB Output is correct
9 Correct 101 ms 12796 KB Output is correct
10 Correct 1 ms 416 KB Output is correct
11 Correct 46 ms 6988 KB Output is correct
12 Correct 227 ms 14912 KB Output is correct
13 Correct 126 ms 13104 KB Output is correct
14 Correct 77 ms 6752 KB Output is correct
15 Correct 58 ms 4872 KB Output is correct