int dis[];bool v[];

void dijkstra(int s)

{

    memset(dis,0x7f,sizeof(dis));ma(v);

    priority_queue<pair<int,int> >q;

    dis[s]=;

    q.push(make_pair(,s));

    while(q.size())

    {

        int x=q.top().second;q.pop();

        if(v[x])continue;

        v[x]=;

        for(int i=f(x);i;i=n(i))

            if(dis[v(i)]>dis[x]+w(i))

            dis[v(i)]=dis[x]+w(i),

            q.push(make_pair(-dis[v(i)],v(i)));

    }

}