dijkstra 堆优化

 #include <iostream>
 #include <vector>
 #include <cstring>
 #include <queue>
 using namespace std;
 struct name
 {
     int end;
     int l;
 };
 bool vis[];
     int n,m,s;
 long long dis[];
 vector <struct name> v[];
 struct node
 {
     int distance;
     int pn;
     friend bool operator <(const node a,const node b)
     {
         return a.distance>b.distance;
     }
 };
 priority_queue <struct node> q;
 void dijstra()
 {
     struct node now;
     now.distance=;
     now.pn=s;
     dis[s]=;
     q.push(now);
     while(!q.empty())
     {
         int x=q.top().pn;
         q.pop();
         if(vis[x]) continue;
         vis[x]=true;
         for(int i=;i<v[x].size();i++)
         {
             if(vis[v[x][i].end]) continue;
             int next=v[x][i].end;
             if(dis[next]>dis[x]+v[x][i].l)
             {
                 dis[next]=dis[x]+v[x][i].l;
                 struct node nextt;
                 nextt.distance=dis[next];
                 nextt.pn=next;
                 q.push(nextt);
             }
         }
     }
     for(int i=;i<=n;i++)
     {
         cout<<dis[i]<<" ";
     }
     return ;
 }
 int main ()
 {

     cin>>n>>m>>s;
     memset(dis,0x3f3f3f3f,sizeof(dis));
     for(int i=;i<=m;i++)
     {
         int x,y,z;
         cin>>x>>y>>z;
         struct name now;
         now.end=y;
         now.l=z;
         v[x].push_back(now);
     }
     dijstra();
     return ;
 }