Submission #1066684

# Submission time Handle Problem Language Result Execution time Memory
1066684 2024-08-20T04:53:50 Z vjudge1 Fire (BOI24_fire) C++17
0 / 100
125 ms 10696 KB
#include <bits/stdc++.h>
using namespace std;
using i64 = long long;

constexpr int mxN = 200'000;
int N, M;
pair<int,int> se[mxN + 1];
vector<int> normal;
i64 dp[3 * mxN + 5];

int getNorm(int x) {
    int lo = 0, hi = (int) normal.size() - 1;
    while (lo <= hi) {
        int mid = lo + (hi - lo) / 2;
        if (normal[mid] == x) return mid;
        else if (normal[mid] < x) lo = mid + 1;
        else hi = mid - 1;
    }
    return -1;
}

void solve() {
    cin >> N >> M;
    for (int i = 0; i < N; i++) {
        cin >> se[i].first >> se[i].second;
        if (se[i].second < se[i].first) {
            se[i].second += M;
            normal.emplace_back(se[i].second - M);
        }
        normal.emplace_back(se[i].first);
        normal.emplace_back(se[i].second);
    }

    sort(normal.begin(), normal.end());
    normal.erase(unique(normal.begin(), normal.end()), normal.end());

    for (int i = 0; i < N; i++) {
        se[i].first = getNorm(se[i].first);
        se[i].second = getNorm(se[i].second);
    }
    sort(se, se + N);

    i64 ans = 1LL * (N + 1) * (N + 1);

    for (int i = 0; i < (int) normal.size(); i++) {
        dp[i] = 1LL * i * (N + 1);
    }

    int id = 0;
    priority_queue<pair<int,int>> pq; // rl
    for (int i = 0; i < (int) normal.size(); i++) {
        for (; id < N && se[id].first == i; id++) {
            pq.push({-se[id].second, -se[id].first});
        }
        if (pq.empty()) {
            cout << "-1\n";
            return;
        }
        dp[i] = min(dp[i], dp[-pq.top().second] + 1);
        for (; !pq.empty() && -pq.top().first == i; pq.pop()) {
            int r = -pq.top().first;
            if (normal[r] >= M) {
                int l = -pq.top().second;
                ans = min(ans, 1 + dp[l] - dp[getNorm(r - M)]);
            }
        }
    }

    if (ans > N) ans = -1;
    cout << ans << '\n';
}

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

    int tc = 1; 
    //cin >> tc;
    while (tc--) {
        solve();
    }

    return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Incorrect 0 ms 348 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Incorrect 0 ms 348 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Incorrect 0 ms 348 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 604 KB Output is correct
2 Correct 0 ms 472 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 348 KB Output isn't correct
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Correct 3 ms 740 KB Output is correct
13 Correct 2 ms 604 KB Output is correct
14 Correct 2 ms 604 KB Output is correct
15 Correct 48 ms 7720 KB Output is correct
16 Correct 108 ms 8132 KB Output is correct
17 Incorrect 125 ms 10696 KB Output isn't correct
18 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Incorrect 0 ms 348 KB Output isn't correct
4 Halted 0 ms 0 KB -