답안 #500698

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
500698	2021-12-31T19:31:34 Z	blue	Firefighting (NOI20_firefighting)	C++17	14 / 100	195 ms	286840 KB

Firefighting

#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;

using ll = long long;
using vll = vector<ll>;
using vvll = vector<vll>;
using vi = vector<int>;

const ll INF = 1'000'000'000'000'000'000LL;


    vvll dist(1+3000, vll(1+3000, INF));

        vvll has_edge(1+3000, vll(1+3000, 0));


            vector< pair<int, ll> > edge[1+3000];

int main()
{
    int N, K;
    cin >> N >> K;

    // for(int i = 1; i <= N; i++) dist[i][i] = 0;


    // vvll edge(1+N, vll(1+N, 0));


    for(int e = 1; e <= N-1; e++)
    {
        int a, b, d;
        cin >> a >> b >> d;
        has_edge[a][b] = has_edge[b][a] = 1;
        // dist[a][b] = dist[b][a] = d;
        // edge[a][b] = edge[b][a] = 1;

        edge[a].push_back({b, d});
        edge[b].push_back({a, d});
    }

    for(int i = 1; i <= N; i++)
    {
        queue<int> tbv;
        tbv.push(i);
        dist[i][i] = 0;
        while(!tbv.empty())
        {
            int u = tbv.front();
            tbv.pop();

            for(auto q: edge[u])
            {
                int v = q.first;
                ll w = q.second;

                if(dist[i][v] < INF) continue;

                dist[i][v] = dist[i][u] + w;
                tbv.push(v);
            }
        }
    }

    // for(int k = 1; k <= N; k++)
    //     for(int i = 1; i <= N; i++)
    //         for(int j = 1; j <= N; j++)
    //             dist[i][j] = min(dist[i][j], dist[i][k] + dist[k][j]);

    vi par(1+N, -1);
    for(int i = 2; i <= N; i++)
    {
        for(int j = 1; j <= N; j++)
        {
            if(j == i) continue;
            if(dist[1][i] == dist[1][j] + dist[j][i] && has_edge[i][j] == 1)
            {
                par[i] = j;
                break;
            }
        }
    }

    if(N <= 1000)
    {
        vector<pair<ll, int> > V;
        for(int i = 1; i <= N; i++) V.push_back({dist[1][i], i});

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

        vi res;

        reverse(V.begin(), V.end());

        vi covered(1+N, 0);

            // if(N >= 100) while(1);

        for(auto q: V)
        {
            int u = q.second;

            if(covered[u]) continue;

            int v = u;
            while(v != 1 && dist[par[v]][u] <= K) v = par[v];

            res.push_back(v);

            for(int i = 1; i <= N; i++)
                if(dist[i][v] <= K)
                    covered[i] = 1;
        }

        cout << int(res.size()) << '\n';
        for(int r: res) cout << r << ' ';
        cout << '\n';
    }



}

Subtask #1
0 / 3.0

#	결과	실행 시간	메모리	Grader output
1	Runtime error	163 ms	286840 KB	Execution killed with signal 11
2	Halted	0 ms	0 KB	-

Subtask #2
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	63 ms	141476 KB	Output is correct
2	Correct	64 ms	141528 KB	Output is correct
3	Correct	56 ms	141548 KB	Output is correct
4	Correct	55 ms	141552 KB	Output is correct
5	Correct	57 ms	141540 KB	Output is correct
6	Correct	55 ms	141444 KB	Output is correct
7	Correct	56 ms	141468 KB	Output is correct
8	Correct	62 ms	141436 KB	Output is correct
9	Correct	57 ms	141424 KB	Output is correct
10	Correct	66 ms	141516 KB	Output is correct
11	Correct	56 ms	141496 KB	Output is correct
12	Correct	61 ms	141508 KB	Output is correct
13	Correct	56 ms	141508 KB	Output is correct
14	Correct	57 ms	141484 KB	Output is correct
15	Correct	56 ms	141428 KB	Output is correct

Subtask #3
9.0 / 9.0

#	결과	실행 시간	메모리	Grader output
1	Correct	59 ms	141528 KB	Output is correct
2	Correct	59 ms	141524 KB	Output is correct
3	Correct	59 ms	141584 KB	Output is correct
4	Correct	58 ms	141508 KB	Output is correct
5	Correct	61 ms	141480 KB	Output is correct
6	Correct	60 ms	141436 KB	Output is correct
7	Correct	57 ms	141428 KB	Output is correct
8	Correct	75 ms	141516 KB	Output is correct
9	Correct	56 ms	141492 KB	Output is correct
10	Correct	67 ms	141464 KB	Output is correct
11	Correct	60 ms	141524 KB	Output is correct
12	Correct	67 ms	141460 KB	Output is correct
13	Correct	57 ms	141508 KB	Output is correct
14	Correct	56 ms	141516 KB	Output is correct
15	Correct	56 ms	141476 KB	Output is correct
16	Correct	57 ms	141508 KB	Output is correct
17	Correct	57 ms	141508 KB	Output is correct
18	Correct	58 ms	141508 KB	Output is correct
19	Correct	56 ms	141544 KB	Output is correct
20	Correct	57 ms	141504 KB	Output is correct
21	Correct	57 ms	141480 KB	Output is correct
22	Correct	57 ms	141536 KB	Output is correct
23	Correct	58 ms	141468 KB	Output is correct
24	Correct	57 ms	141472 KB	Output is correct
25	Correct	58 ms	141428 KB	Output is correct
26	Correct	58 ms	141476 KB	Output is correct