void dijkstra(int src , vector < int >& dis, int n)
{
    for(int i = 1 ; i <= n ; i++) dis[i] = MAX;
    priority_queue < pair < int , int > > tempo;
    tempo.push({0 , src});
    while(!tempo.empty()){
        pair < int , int > p = tempo.top();
        tempo.pop();
        int node = p.second;
        if(-p.first > dis[node]) continue;
        for(auto adj:edg[node]){
            int a = adj.first , w = adj.second;
            int val = dis[node] + w;
            if(val < dis[a]){
                dis[a] = val;
                tempo.push({-val , a});
            }
        }
    }
} /// O(m * log(m) ) ; m = number of edges