oj.uz

Submission #838689

# Submission time Handle Problem Language Result Execution time Memory
838689 2023-08-27T15:12:48 Z skittles1412 Event Hopping (BOI22_events) C++17
25 / 100
 1500 ms 8156 KB 
#include "bits/extc++.h"

using namespace std;

template <typename T, typename... U>
void dbgh(const T& t, const U&... u) {
    cerr << t;
    ((cerr << " | " << u), ...);
    cerr << endl;
}

#ifdef DEBUG
#define dbg(...)                                              \
    cerr << "L" << __LINE__ << " [" << #__VA_ARGS__ << "]: "; \
    dbgh(__VA_ARGS__)
#else
#define dbg(...)
#define cerr   \
    if (false) \
    cerr
#endif

#define endl "\n"
#define long int64_t
#define sz(x) int(std::size(x))

void solve() {
    int n, q;
    cin >> n >> q;

    vector<pair<int, int>> arr(n);
    for (auto& [l, r] : arr) {
        cin >> l >> r;
    }

    int logn = __lg(n);

    vector<vector<int>> lift(logn + 1, vector<int>(n));
    for (int i = 0; i < n; i++) {
        pair<int, int> c_opt {int(1e9), -1};

        for (int j = 0; j < n; j++) {
            if (arr[i].first <= arr[j].second &&
                arr[j].second <= arr[i].second) {
                c_opt = min(c_opt, {arr[j].first, j});
            }
        }

        if (c_opt.first >= arr[i].first) {
            lift[0][i] = -1;
        } else {
            lift[0][i] = c_opt.second;
        }
    }

    for (int i = 1; i <= logn; i++) {
        for (int j = 0; j < n; j++) {
            if (lift[i - 1][j] == -1) {
                lift[i][j] = -1;
            } else {
                lift[i][j] = lift[i - 1][lift[i - 1][j]];
            }
        }
    }

    while (q--) {
        int u, v;
        cin >> u >> v;
        u--;
        v--;

        if (u == v) {
            cout << 0 << endl;
            continue;
        }

        int ans = 0;
        for (int i = logn; i >= 0; i--) {
            int nv = lift[i][v];
            if (nv != -1 && arr[u].second < arr[nv].first) {
                v = nv;
                ans += 1 << i;
            }
        }
        if (arr[u].second < arr[v].first) {
            v = lift[0][v];
            ans++;
        }
        // int ql = arr[v].first, qr = arr[v].second, ans = 0;

        // while (ql > arr[u].second) {
        //     int n_opt = 1e9;

        //     for (auto& [l, r] : arr) {
        //         if (ql <= r && r <= qr) {
        //             n_opt = min(n_opt, l);
        //         }
        //     }

        //     if (n_opt >= ql) {
        //         break;
        //     }
        //     ans++;
        //     ql = n_opt;
        // }

        if (v != -1 && arr[v].first <= arr[u].second &&
            arr[u].second <= arr[v].second) {
            ans++;
            cout << ans << endl;
        } else {
            cout << "impossible" << endl;
        }
    }
}

int main() {
    cin.tie(nullptr);
    cin.exceptions(ios::failbit);
    ios_base::sync_with_stdio(false);
    solve();
}

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Execution timed out 1578 ms 8152 KB Time limit exceeded
3 Halted 0 ms 0 KB -

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 3 ms 340 KB Output is correct
4 Correct 3 ms 340 KB Output is correct
5 Correct 3 ms 340 KB Output is correct
6 Correct 3 ms 340 KB Output is correct
7 Correct 5 ms 340 KB Output is correct
8 Correct 3 ms 340 KB Output is correct
9 Correct 2 ms 340 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 3 ms 340 KB Output is correct
4 Correct 3 ms 340 KB Output is correct
5 Correct 3 ms 340 KB Output is correct
6 Correct 3 ms 340 KB Output is correct
7 Correct 5 ms 340 KB Output is correct
8 Correct 3 ms 340 KB Output is correct
9 Correct 2 ms 340 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 3 ms 340 KB Output is correct
13 Correct 3 ms 340 KB Output is correct
14 Correct 3 ms 340 KB Output is correct
15 Correct 4 ms 340 KB Output is correct
16 Correct 4 ms 340 KB Output is correct
17 Correct 3 ms 340 KB Output is correct
18 Correct 2 ms 340 KB Output is correct
19 Correct 109 ms 1864 KB Output is correct
20 Correct 95 ms 2132 KB Output is correct
21 Correct 96 ms 2272 KB Output is correct
22 Correct 106 ms 2408 KB Output is correct
23 Correct 121 ms 2256 KB Output is correct
24 Correct 105 ms 2256 KB Output is correct
25 Correct 94 ms 1872 KB Output is correct

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 3 ms 340 KB Output is correct
4 Correct 3 ms 340 KB Output is correct
5 Correct 3 ms 340 KB Output is correct
6 Correct 3 ms 340 KB Output is correct
7 Correct 5 ms 340 KB Output is correct
8 Correct 3 ms 340 KB Output is correct
9 Correct 2 ms 340 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 3 ms 340 KB Output is correct
13 Correct 3 ms 340 KB Output is correct
14 Correct 3 ms 340 KB Output is correct
15 Correct 4 ms 340 KB Output is correct
16 Correct 4 ms 340 KB Output is correct
17 Correct 3 ms 380 KB Output is correct
18 Correct 2 ms 372 KB Output is correct
19 Execution timed out 1581 ms 8156 KB Time limit exceeded
20 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1574 ms 8148 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Execution timed out 1578 ms 8152 KB Time limit exceeded
3 Halted 0 ms 0 KB -