void dijikstra()
{
    memset(dist,0x3f,sizeof dist);
    priority_queue<PII, vector<PII>, greater<PII>> heap;
    heap.push({0,1});
    dist[1] = 0;

    while(heap.size())
    {
        auto t = q.top(); q.pop();
        int d = t.x, ver = t.y;
        if(st[ver] == true) continue;
        st[ver] = true;

        for(int i = h[ver]; i != -1; i=ne[i])
        {
            int j = e[i];
            if(dist[j] > d + w[i])
            {
                dist[j] = d + w[i];
                heap.push({dist[j],j});
            }
        }
    }


}