求条轩关

#include<bits/stdc++.h>
using namespace std;
struct bus{
    int dian,money;
};
int n,m,cnt,dis1[1000001],dis2[1000001],vis1[1000001],vis2[1000001];
vector<bus> g1[1000001],g2[1000001];
bool operator<(bus a,bus b){
    return a.money>b.money;
}
priority_queue<bus,vector<bus>,less<bus> > q1,q2;
void dijkstra1(int start1){
    for (int i=1;i<=n;i++){
        vis1[i]=0;
        dis1[i]=1e9;
    }
    dis1[start1]=0;
    q1.push({start1,0});
    while(!q1.empty()){
        bus temp1=q1.top();
        q1.pop();
        if(vis1[temp1.dian]==1) continue;
        vis1[temp1.dian]=1;
        for (int i=0;i<g1[temp1.dian].size();i++){
            bus tem1=g1[temp1.dian][i];
            if(dis1[tem1.dian]>dis1[temp1.dian]+tem1.money){
                dis1[tem1.dian]=dis1[temp1.dian]+tem1.money;
                q1.push({tem1.dian,dis1[tem1.dian]});
            }
        }
    }
}
void dijkstra2(int start2){
    for (int i=1;i<=n;i++){
        vis2[i]=0;
        dis2[i]=1e9;
    }
    dis2[start2]=0;
    q2.push({start2,0});
    while(!q2.empty()){
        bus temp2=q2.top();
        q2.pop();
        if(vis2[temp2.dian]==1) continue;
        vis2[temp2.dian]=1;
        for (int i=0;i<g2[temp2.dian].size();i++){
            bus tem2=g2[temp2.dian][i];
            if(dis2[tem2.dian]>dis2[temp2.dian]+tem2.money){
                dis2[tem2.dian]=dis2[temp2.dian]+tem2.money;
                q2.push({tem2.dian,dis2[tem2.dian]});
            }
        }
    }
}

int main()
{
    cin>>n>>m;
    for (int i=1;i<=m;i++){
        int u,v,w;
        cin>>u>>v>>w;
        g1[u].push_back({v,w});
        g2[v].push_back({u,w});
    }
    dijkstra1(1);
    dijkstra2(1);
    for (int i=1;i<=n;i++){
        cnt+=dis1[i];
        cnt+=dis2[i];
//      cout<<dis1[i]<<" "<<dis2[i]<<endl;
    }
    cout<<cnt;

    return 0;
}