Submission #1130431

#	Time	Username	Problem	Language	Result	Execution time	Memory
1130431		enzy	Commuter Pass (JOI18_commuter_pass)	C++20	Compilation error	0 ms	0 KiB

commuter_pass

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int maxn=1e5+10;
const int inf=1e18+10;
vector<pair<int,int>>adj[maxn];
int dist[maxn][4], n, marc[maxn];
void dijkstra(int x, int t,int dir){
    for(int i=1;i<=n;i++) dist[i][t]=inf;
    dist[x][t]=0;
    set<pair<int,int>>s;
    for(int i=1;i<=n;i++) s.insert({dist[i][t],i});
    while(!s.empty()){
        auto f=s.begin();
        int u=f->second;
        used[u][t]++;
        s.erase(f);
        for(auto p : adj[u]){
            int viz=p.first, w=p.second;
            if(marc[u]&&marc[viz]&&dist[u][dir]+w==dist[viz][dir]&&dist[u][t]<dist[viz][t]){
                // estou usando uma aresta já DIRECIONADA do commuter pass, então passo de graça
                s.erase({dist[viz][t],viz});
                dist[viz][t]=dist[u][t];
                s.insert({dist[viz][t],viz});
            }
            if(dist[u][t]+w<dist[viz][t]){
                // estou utilizando uma aresta normalmente, então tenho que pagar
                s.erase({dist[viz][t],viz});
                dist[viz][t]=dist[u][t]+w;
                s.insert({dist[viz][t],viz});
            }
        }
    }
}
signed main()
{
    ios_base::sync_with_stdio(false); cin.tie(NULL);
    int m, s, t, u, v; cin >> n >> m >> s >> t >> u >> v;
    for(int i=1;i<=m;i++){
        int a, b, c; cin >> a >> b >> c;
        adj[a].push_back({b,c});
        adj[b].push_back({a,c});
    }
    dijkstra(s,2,0);
    dijkstra(t,3,0);
    int best=dist[t][2];
    for(int i=1;i<=n;i++) if(dist[i][2]+dist[i][3]==best) marc[i]++;
    dijkstra(u,0,2); // direcionando todas as arestas do commuter pass de S->T
    dijkstra(u,1,3); // direcionando todas as arestas do commuter pass de T->S
    cout << min(dist[v][0],dist[v][1]) << endl;
    return 0;
}

Compilation message (stderr)

commuter_pass.cpp: In function 'void dijkstra(long long int, long long int, long long int)':
commuter_pass.cpp:16:9: error: 'used' was not declared in this scope
   16 |         used[u][t]++;
      |         ^~~~