Submission #249467

#	Time	Username	Problem	Language	Result	Execution time	Memory
249467		cheeheng	Meetings (JOI19_meetings)	C++14	29 / 100	3094 ms	9104 KiB

meetings

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

int lca[2005][2005];

vector<int> AdjList[2005];

vector<int> toposort;
bool visited[2005];

void dfs(int u){
    if(visited[u]){return;}
    visited[u] = true;
    //printf("dfs(%d)\n", u);
    for(int v: AdjList[u]){
        dfs(v);
    }
    toposort.push_back(u);
}

void Solve(int N) {
    lca[0][0] = 0;
    for(int i = 1; i < N; i ++){
        lca[0][i] = 0;
        lca[i][0] = 0;
    }
    for(int i = 1; i < N; i ++){
        lca[i][i] = i;
        for(int j = i+1; j < N; j ++){
            lca[i][j] = Query(0, i, j);
            lca[j][i] = lca[i][j];
        }
    }

    if(N > 300){
        throw;
    }

    for(int i = 0; i < N; i ++){
        for(int j = 0; j < N; j ++){
            if(i == j){continue;}
            if(lca[i][j] == i){
                AdjList[i].push_back(j);
            }
        }
    }
    dfs(0);
    reverse(toposort.begin(), toposort.end());

    /*printf("Toposort: ");
    for(int i = 0; i < N; i ++){
        printf("%d ", toposort[i]);
    }
    printf("\n");*/

    for(int i = N-1; i >= 1; i --){
        for(int j = i-1; j >= 0; j --){
            int u = toposort[i];
            int v = toposort[j];
            if(lca[u][v] == v){
                Bridge(min(u, v), max(u, v));
                break;
            }
        }
    }
    return;
}

• Subtask 1: 7 / 7
• Subtask 2: 10 / 10
• Subtask 3: 12 / 12
• Subtask 4: 0 / 71