Submission #1021846

#	Time	Username	Problem	Language	Result	Execution time	Memory
1021846		m5588ohammed	Valley (BOI19_valley)	C++14	0 / 100	87 ms	11204 KiB

valley

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define endl "\n"
int n,S,E,q,U,V,x,l;
vector <array<int,2>> v[100001],edges;
priority_queue <array<int,2>> qu;
int dis[100001],shops[100001];
void dij(){
    for(int i=1;i<=n;i++) dis[i]=-1;
    dis[x]=0;
    qu.push({0,x});
    while(!qu.empty()){
        auto [mydis,i]=qu.top();
        mydis*=-1;
        qu.pop();
        if(mydis>dis[i]&&dis[i]!=-1) continue;
        for(auto [j,w]:v[i]){
            if((i==U&&j==V)||(i==V&&j==U)) continue;
            if(dis[j]>mydis+w||dis[j]==-1){
                dis[j]=mydis+w;
                qu.push({dis[j]*-1,j});
            } 
        }
    }
    return;
}
void calc1(){
    while(q--){
        cin>>l>>x;
        U=edges[l-1][0];
        V=edges[l-1][1];
        dij();
        if(dis[E]!=-1){ cout<<"escaped"<<endl;continue;}
        int mn=1e14;
        for(int i=0;i<S;i++) if(dis[shops[i]]!=-1) mn=min(mn,dis[shops[i]]);
        if(mn==1e14) cout<<"oo"<<endl;
        else cout<<mn<<endl;
    }
}
signed main()
{
    cin>>n>>S>>q>>E;
    for(int i=0;i<n-1;i++){
        int a,b,c;
        cin>>a>>b>>c;
        v[a].push_back({b,c});
        v[b].push_back({a,c});
        edges.push_back({a,b});
    }
    for(int i=0;i<S;i++) cin>>shops[i];
    if(n<=1000&&q<=1000) calc1();
    return 0;
}

Compilation message (stderr)

valley.cpp: In function 'void dij()':
valley.cpp:14:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   14 |         auto [mydis,i]=qu.top();
      |              ^
valley.cpp:18:18: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   18 |         for(auto [j,w]:v[i]){
      |                  ^

• Subtask 1: 0 / 9
• Subtask 2: 0 / 27
• Subtask 3: 0 / 23
• Subtask 4: 0 / 41