Submission #599056

#	Time	Username	Problem	Language	Result	Execution time	Memory
599056		SlavicG	Event Hopping (BOI22_events)	C++17	10 / 100	1596 ms	128276 KiB

events

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

const int N = 5001;
int dist[N][N];
vector<int> adj[N];
void bfs(int start) {
    queue<int> q; q.push(start);
    while(!q.empty()) {
        int u = q.front();
        q.pop();
        for(int v: adj[u]) {
            if(dist[start][v] == -1) {
                dist[start][v] = dist[start][u] + 1;
                q.push(v);
            }
        }
    }
}
int main() {
    for(int i = 0; i < N; ++i) for(int j = 0; j < N; ++j) dist[i][j] = (i == j ? 0 : -1);
    int n, q; cin >> n >> q;
    vector<int> l(n), r(n);
    for(int i = 0; i < n; ++i) cin >> l[i] >> r[i];
    for(int i = 0; i < n; ++i) {
        for(int j = 0; j < n; ++j) {
            if(i == j) continue;
            if(r[i] >= l[j] && r[i] <= r[j]) {
                adj[i].push_back(j);
            }
        }
    }
    for(int i = 0; i < n; ++i) bfs(i);
    while(q--) {
        int a, b; cin >> a >> b; --a, --b;
        if(dist[a][b] == -1) cout << "impossible\n";
        else cout << dist[a][b] << "\n";
    }
}

• Subtask 1: 0 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30