Submission #649735

#	Time	Username	Problem	Language	Result	Execution time	Memory
649735		Uzouf	Commuter Pass (JOI18_commuter_pass)	C++14	0 / 100	288 ms	19112 KiB

commuter_pass

#include <bits/stdc++.h>
using namespace std;
#define int long long

signed main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int n,m; cin>>n>>m;
    int s,t,u,v; cin>>s>>t>>u>>v;
    vector<vector<pair<int,int> > > vv(n+5);

    for (int i=0;i<m;i++) {
        int a,b,c; cin>>a>>b>>c;
        vv[a].push_back({b,c});
        vv[b].push_back({a,c});
    }

    int diss[n+5],dist[n+5],disv[n+5],par[n+5];
    for (int i=0;i<=n;i++) {
        diss[i]=dist[i]=disv[i]=1e18; par[i]=-1;
    }

    priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > q;
    q.push({0,s}); diss[s]=0; par[s]=s;
    while (!q.empty()) {
        int c=q.top().first,i=q.top().second;
        q.pop();
        if (c>diss[i]) continue;
        for (int j=0;j<vv[i].size();j++) {
            int ii=vv[i][j].first,cc=vv[i][j].second;
            int nwc=c+cc;
            if (diss[ii]>nwc) {
                diss[ii]=nwc;
                q.push({nwc,ii});
                par[ii]=i;
            }
        }
    }

    int indx=t;
    while (indx!=s) {
        for (int i=0;i<vv[indx].size();i++) {
            if (vv[indx][i].first==par[indx]) vv[indx][i].second=0;
        }
        for (int i=0;i<vv[par[indx]].size();i++) {
            if (vv[par[indx]][i].first==indx) vv[par[indx]][i].second=0;
        }
        indx=par[indx];
    }


    q.push({0,v}); disv[v]=0;
    while (!q.empty()) {
        int c=q.top().first,i=q.top().second;
        q.pop();
        if (c>disv[i]) continue;
        for (int j=0;j<vv[i].size();j++) {
            int ii=vv[i][j].first,cc=vv[i][j].second;
            int nwc=c+cc;
            if (disv[ii]>nwc) {
                disv[ii]=nwc;
                q.push({nwc,ii});
                par[ii]=i;
            }
        }
    }

    if (s!=u) {
            cout<<diss[v]; return 0;
    }

    q.push({0,t}); dist[t]=0;
    while (!q.empty()) {
        int c=q.top().first,i=q.top().second;
        q.pop();
        if (c>dist[i]) continue;
        for (int j=0;j<vv[i].size();j++) {
            int ii=vv[i][j].first,cc=vv[i][j].second;
            int nwc=c+cc;
            if (dist[ii]>nwc) {
                dist[ii]=nwc;
                q.push({nwc,ii});
                par[ii]=i;
            }
        }
    }

    int ans=1e18;
    for (int i=1;i<=n;i++) {
        if (diss[i]+dist[i]==diss[t]) {
            ans=min(ans,disv[i]);
        }
    }
    cout<<ans;
}

Compilation message (stderr)

commuter_pass.cpp: In function 'int main()':
commuter_pass.cpp:29:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |         for (int j=0;j<vv[i].size();j++) {
      |                      ~^~~~~~~~~~~~~
commuter_pass.cpp:42:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |         for (int i=0;i<vv[indx].size();i++) {
      |                      ~^~~~~~~~~~~~~~~~
commuter_pass.cpp:45:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |         for (int i=0;i<vv[par[indx]].size();i++) {
      |                      ~^~~~~~~~~~~~~~~~~~~~~
commuter_pass.cpp:57:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   57 |         for (int j=0;j<vv[i].size();j++) {
      |                      ~^~~~~~~~~~~~~
commuter_pass.cpp:77:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   77 |         for (int j=0;j<vv[i].size();j++) {
      |                      ~^~~~~~~~~~~~~

• Subtask 1: 0 / 16
• Subtask 2: 0 / 15
• Subtask 3: 0 / 24
• Subtask 4: 0 / 45