Dijkstra模版

struct Edge{
    int from,to,dist;
    Edge(int u,int v,int d):from(u),to(v),dist(d){}
};

struct Dijkstra{
    int n,m;
    vector<Edge> edges;
    vector<int> G[maxn];
    bool done[maxn];
    int d[maxn];
    int p[maxn];
   // int my[maxn];

    void init(int n){
        this->n=n;
        for(int i=0;i<n;++i) G[i].clear();
        edges.clear();
    }

    void AddEdge(int from,int to,int dist){
        edges.push_back(Edge(from,to,dist));
        m=edges.size();
        G[from].push_back(m-1);
    }

    struct HeadNode{
        int d,u,my;
        bool operator <(const HeadNode & rhs) const {
            return d>rhs.d/*||(d==rhs.d&&my<rhs.my)*/;
        }
    };

    void dijkstra(int s){
        priority_queue<HeadNode> q;
        for(int i=0;i<n;++i) {
            d[i]=INF;
          //  my[i]=0;
        }
        d[s]=0;
      //  my[s]=ny[s];
        memset(done, 0, sizeof(done));
        q.push({0,s/*,my[s]*/});
        while(!q.empty()){
            HeadNode x=q.top();q.pop();
            int u=x.u;
            if(done[u]) continue;
          //  cout<<x.d<<" "<<x.u<<" "<<x.my<<endl;
            done[u]=true;
            for(int i=0;i<G[u].size();++i){
                Edge &e=edges[G[u][i]];
                if(d[e.to]>d[u]+e.dist){
                    d[e.to]=d[u]+e.dist;
                    p[e.to]=G[u][i];
               //     my[e.to]=my[u]+ny[e.to],my[e.to];
                    q.push({d[e.to],e.to/*,my[e.to]*/});
                }
            }
        }
    }
};