oj.uz

Submission #745866

# Submission time Handle Problem Language Result Execution time Memory
745866 2023-05-21T08:53:37 Z vjudge1 Event Hopping (BOI22_events) C++14
10 / 100
 1500 ms 61840 KB 
#include <bits/stdc++.h>

using namespace std;
using ll = long long;


int main(){

    int n, q;
    cin >> n >> q;
    vector<pair<int, int> > inter(n);


    for (int i = 0; i < n; i++){
        cin >> inter[i].first >> inter[i].second;
    }

    if (n > 1000){
        vector<pair<pair<int, int>, int> > elso(n);
        vector<int> hely(n);
        for (int i = 0; i < n; i++){
            elso[i] = make_pair(inter[i], i);
        }

        sort(elso.begin(), elso.end());

        for (int i = 0; i < n; i++){
            hely[elso[i].second] = i;
        }
        
        vector<ll> tav(n, -1); 
        for (ll i = 0; i < n; i++){
            if (tav[i] != -1) continue;
            queue<ll> q;
            q.push(i);
            tav[i] = i*10000000;
            while(!q.empty()){
                ll pos = q.front();
                q.pop();
                if (pos != n - 1 && elso[pos].first.second <= elso[pos + 1].first.second && elso[pos].first.second >= elso[pos + 1].first.first){
                    tav[pos + 1] = tav[pos] + 1;
                    q.push(pos + 1);
                }
            }
        }
        for (int i = 0; i < q; i++){
            int a, b;
            cin >> a >> b;
            a--, b--;
            a = hely[a];
            b = hely[b];
            if (tav[b] - tav[a] < 0 || tav[b] - tav[a] > 999999){
                cout << "impossible" << endl;
            }
            else cout << tav[b] - tav[a] << endl;
        }
    }


    vector<vector<int> > graph(n);

    for (int i = 0; i < n; i++){
        for (int j = 0; j < n; j++){
            if (i == j) continue;
            if (inter[i].second <= inter[j].second && inter[i].second >= inter[j].first){
                graph[i].push_back(j);
            }
        }
    }


    // for (int i = 0; i < n; i++){
    //     for (int x : graph[i]) cout << x << " ";
    //     cout << endl;
    // }

    for (int i = 0; i < q; i++){
        int s, e;
        cin >> s >> e;
        s--, e--;

        queue<int> q;
        q.push(s);
        vector<int> tav(n, -1); 
        tav [s] = 0;
        while(!q.empty()){
            int pos = q.front();
            q.pop();
            for (int x : graph[pos]){
                if (tav[x] == -1){
                    tav[x] = tav[pos] + 1;
                    q.push(x);
                }
            }
        }
        if (tav[e] == -1) {
            cout << "impossible" << endl;
        }
        else cout << tav[e] << endl;
    }


    return 0;
}

/*

5 2
1 3
2 4
4 7
7 9
3 7
1 4
3 2

*/

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Execution timed out 1574 ms 4172 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 7 ms 340 KB Output is correct
4 Correct 6 ms 352 KB Output is correct
5 Correct 7 ms 340 KB Output is correct
6 Correct 13 ms 1108 KB Output is correct
7 Correct 26 ms 1876 KB Output is correct
8 Correct 25 ms 2928 KB Output is correct
9 Correct 105 ms 4308 KB Output is correct

Subtask #3
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 7 ms 340 KB Output is correct
4 Correct 6 ms 352 KB Output is correct
5 Correct 7 ms 340 KB Output is correct
6 Correct 13 ms 1108 KB Output is correct
7 Correct 26 ms 1876 KB Output is correct
8 Correct 25 ms 2928 KB Output is correct
9 Correct 105 ms 4308 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 9 ms 340 KB Output is correct
13 Correct 6 ms 340 KB Output is correct
14 Correct 6 ms 340 KB Output is correct
15 Correct 11 ms 1108 KB Output is correct
16 Correct 29 ms 1876 KB Output is correct
17 Correct 25 ms 2916 KB Output is correct
18 Correct 110 ms 4272 KB Output is correct
19 Runtime error 397 ms 61840 KB Execution killed with signal 11
20 Halted 0 ms 0 KB -

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 7 ms 340 KB Output is correct
4 Correct 6 ms 352 KB Output is correct
5 Correct 7 ms 340 KB Output is correct
6 Correct 13 ms 1108 KB Output is correct
7 Correct 26 ms 1876 KB Output is correct
8 Correct 25 ms 2928 KB Output is correct
9 Correct 105 ms 4308 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 8 ms 340 KB Output is correct
13 Correct 6 ms 344 KB Output is correct
14 Correct 7 ms 340 KB Output is correct
15 Correct 15 ms 1108 KB Output is correct
16 Correct 22 ms 1840 KB Output is correct
17 Correct 24 ms 2900 KB Output is correct
18 Correct 108 ms 4308 KB Output is correct
19 Execution timed out 1590 ms 3440 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 1549 ms 4168 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 1574 ms 4172 KB Time limit exceeded
3 Halted 0 ms 0 KB -