Submission #783483

#	Time	Username	Problem	Language	Result	Execution time	Memory
783483		8pete8	Commuter Pass (JOI18_commuter_pass)	C++14	0 / 100	191 ms	19488 KiB

commuter_pass

#include<iostream>
#include<stack>
#include<map>
#include<vector>
#include<string>
#include<unordered_map>
#include <queue>
#include<cstring>
#include<limits.h>
#include<cmath>
#include<set>
#include<algorithm>
#include<bitset>
using namespace std;
#define ll long long
#define f first
#define endl "\n"
#define s second
#define pii pair<int,int>
#define ppii pair<pii,pii>
#define pb push_back
#define p push
#define fastio ios::sync_with_stdio(false);cin.tie(NULL);
using namespace std;
const int mxn=1e5;
int n,m,s,t,u,v;
#define int long long
vector<pii>adj[mxn+10];
bitset<mxn+10>vis;
struct dat{
    ll c,d,pa;
    bool operator<(const dat&a)const{return d<a.d;}
};
void dijk(int st,vector<int>&dist){
    priority_queue<pii,vector<pii>,greater<pii>>pq;
    pq.p({0,st});
    dist[st]=0;
    while(!pq.empty()){
        int cur=pq.top().s;
        pq.pop();
        if(vis[cur])continue;
        vis[cur]=true;
        for(auto i:adj[cur]){
            if(dist[i.f]==-1||dist[i.f]>dist[cur]+i.s){
                dist[i.f]=dist[cur]+i.s,pq.p({dist[i.f],i.f});
            }
        }
    }
    vis.reset();
}
int32_t main(){
    fastio
    cin>>n>>m>>s>>t>>u>>v;
    while(m--){
        int a,b,c;cin>>a>>b>>c;
        adj[a].pb({b,c});
        adj[b].pb({a,c});
    }
    vector<int>dist1(n+1,-1);
    vector<int>dist2(n+1,-1);
    dijk(u,dist1);
    dijk(v,dist2);
    priority_queue<dat>pq;
    pq.p({s,0,-1});
    vector<pair<int,pii>>dist(n+1,{-1,{-1,-1}});
    dist[s]={0,{dist1[s],dist2[s]}};
    while(!pq.empty()){
        dat cur=pq.top();
        pq.pop();
        if(vis[cur.c])continue;
        vis[cur.c]=true;
        if(cur.pa!=-1){
            dist[cur.c].s.f=min(dist[cur.c].s.f,dist[cur.pa].s.f);
            dist[cur.c].s.s=min(dist[cur.c].s.s,dist[cur.pa].s.s);
        }
        for(auto i:adj[cur.c]){
            if(dist[i.f].f==-1||dist[i.f].f>dist[cur.c].f+i.s){
                int ndu=min(dist[cur.c].s.f,dist1[i.f]),ndv=min(dist[cur.c].s.s,dist2[i.f]);
                dist[i.f]={dist[cur.c].f+i.s,{ndu,ndv}};
                pq.p({i.f,dist[i.f].f,cur.c});
            }
            else if(dist[i.f].f==dist[cur.c].f+i.s){
                dist[i.f].s.f=min(dist[i.f].s.f,dist[cur.c].s.f);
                dist[i.f].s.f=min(dist[i.f].s.s,dist[cur.c].s.s);
            }
        }
    }
    cout<<min(dist[t].s.f+dist[t].s.s,dist1[v]);
}

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