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Submission #943762

# Submission time Handle Problem Language Result Execution time Memory
943762 2024-03-11T20:34:24 Z tmarcinkevicius Event Hopping (BOI22_events) C++14
0 / 100
 1500 ms 13364 KB 
#include <bits/stdc++.h>  
using namespace std;

#define int int64_t
typedef pair<int,int> pii;
typedef vector<int> vii;
#define MP make_pair
#define PB push_back
#define f first
#define s second
#define INF 2e18
#define fast_io() ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define all(x) (x).begin(), (x).end()
#define sz(x) ((ll)(x).size())



struct Interval
{
    int id;
    pii range;
};

int N, Q;
vector<Interval> intervals;
vector<pii> queries;

vector<int> adjBest;
vector<set<int>> adjAll;

int32_t main()
{
    fast_io();

    cin >> N >> Q;
    intervals = vector<Interval>(N + 1);
    adjBest = vector<int>(N + 1);
    adjAll = vector<set<int>>(N + 1);

    //vector<pii> endPoints;
    // { time, 0 for start / 1 for end }

    for (int i = 1; i <= N; i++)
    {
        Interval inter;
        cin >> inter.range.f >> inter.range.s;

        inter.id = i + 1;
        intervals[i] = inter;

        //endPoints.push_back({inter.range.f, 0});
        //endPoints.push_back({inter.range.s, 1});
    }

    queries = vector<pii>(Q);
    for (int i = 0; i < Q; i++)
    {
        cin >> queries[i].f >> queries[i].s;
    }

    //sort(all(endPoints));

    

    //sort(all(intervals), [](Interval a, Interval b)
    //    { return a.range.s < b.range.s; });

    for (int i = 1; i <= N; i++)
    {
        for (int j = 1; j <= N; j++)
        {
            if (i == j)
                continue;

            if (intervals[i].range.s >= intervals[j].range.f && 
                intervals[i].range.s <= intervals[j].range.s)
            {
                adjAll[i].insert(j);
            }
        }
    }


    for (int i = 1; i <= N; i++)
    {
        int bestE = -1;
        int bestId = -1;

        //cout << "adjAll[" << i << "]: {";
        for (int j : adjAll[i])
        {
            //cout << j << " ";
            if (intervals[j].range.s > bestE)
            {
                bestId = j;
                bestE = intervals[j].range.s;
            }
        }
        //cout << "}\n";

        adjBest[i] = bestId;
    }

    for (int q = 0; q < Q; q++)
    {
        if (queries[q].f == queries[q].s)
        {
            cout << 0 << '\n';
            continue;
        }
        vector<int> dis(N + 1, INF);
        queue<int> qu;
        qu.push(queries[q].f);
        dis[queries[q].f] = 0;
        bool impossible = true;

        while (!qu.empty())
        {
            int fr = qu.front();
            qu.pop();
            //cout << "at: " << fr << '\n';

            if (adjAll[fr].count(queries[q].s))
            {
                //cout << "can go already\n";
                cout << dis[fr] + 1 << '\n';
                impossible = false;
                break;
            }

            if (adjBest[fr] != -1 && dis[adjBest[fr]] == INF)
            {
                dis[adjBest[fr]] = dis[fr] + 1;
                qu.push(adjBest[fr]);
            }
        }

        if (impossible)
        {
            cout << "impossible\n";
        }
    }
}

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Execution timed out 1580 ms 13352 KB Time limit exceeded
3 Halted 0 ms 0 KB -

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 5 ms 556 KB Output is correct
4 Correct 4 ms 572 KB Output is correct
5 Incorrect 4 ms 568 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 5 ms 556 KB Output is correct
4 Correct 4 ms 572 KB Output is correct
5 Incorrect 4 ms 568 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 5 ms 556 KB Output is correct
4 Correct 4 ms 572 KB Output is correct
5 Incorrect 4 ms 568 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1508 ms 13364 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 348 KB Output is correct
2 Execution timed out 1580 ms 13352 KB Time limit exceeded
3 Halted 0 ms 0 KB -