제출 #526722

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
526722		Hydroxic_Acid	Autobus (COCI22_autobus)	C++14	0 / 70	325 ms	484 KiB

Main

#include <iostream>
#include <cstring>
#include <vector>
#include <queue>
using namespace std;
#define ll long long

int n, m, q, k;
vector<pair<int, int> > adjl[75];
bool visited[75];
int adjm[75][75];

bool check(ll time, int c, int d){
    memset(visited, false, sizeof(visited));
    queue<pair<int, pair<int, ll> > > q;
    q.push(make_pair(c, make_pair(0, 0)));
    while(!q.empty()){
        pair<int, pair<int, int> > iii = q.front(); q.pop();
        if(iii.second.first > k) continue;
        if(iii.second.second > time) continue;
        if(iii.first == d) return true;
        if(visited[iii.first]) continue;
        visited[iii.first] = true;
        for(int i = 0; i < (int)adjl[iii.first].size(); i++){
            q.push(make_pair(adjl[iii.first][i].first, make_pair(iii.second.first + 1, iii.second.second + adjl[iii.first][i].second)));
        }
    }
    return false;
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n >> m;
    for(int i = 0; i < m; i++){
        int a, b, t; cin >> a >> b >> t;
        if(adjm[a][b] == 0) adjm[a][b] = t;
        else adjm[a][b] = min(adjm[a][b], t);
    }
    ll tmax = 0;
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= n; j++){
            if(adjm[i][j] != 0){
                adjl[i].push_back(make_pair(j, adjm[i][j]));
                tmax += adjm[i][j];
                adjm[i][j] = 1;
            }
        }
    }

    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= n; j++){
            if(adjm[i][j] != 1){
                adjm[i][j] = 1000000001;
                if(i == j) adjm[i][j] = 0;
            }
        }
    }
    
    cin >> k >> q;
    for(int x = 1; x <= n; x++){
        for(int y = 1; y <= n; y++){
            for(int z = 1; z <= n; z++){
                adjm[y][z] = min(adjm[y][z], adjm[y][x] + adjm[x][z]);
            }
        }
    }

    for(int i = 0; i < q; i++){
        int c, d; cin >> c >> d;
        if(adjm[c][d] > k){
            cout << -1 << "\n"; continue;
        }
        ll lower = 0;
        ll upper = tmax;
        while(lower < upper){
            ll mid = (ll)(lower + upper) / 2;
            if(check(mid, c, d))upper = mid;
            else lower = mid + 1;
        }
        cout << lower << "\n";
    }
    
}

• Subtask 1: 0 / 15
• Subtask 2: 0 / 15
• Subtask 3: 0 / 25
• Subtask 4: 0 / 15