dijkstra algorithm in nlogn time cp algorithm
const int INF = 1000000000;
vector<vector<pair<int, int>>> adj;
void dijkstra(int s, vector<int> & d, vector<int> & p) {
int n = adj.size();
d.assign(n, INF);
p.assign(n, -1);
d[s] = 0;
set<pair<int, int>> q;
q.insert({0, s});
while (!q.empty()) {
int v = q.begin()->second;
q.erase(q.begin());
for (auto edge : adj[v]) {
int to = edge.first;
int len = edge.second;
if (d[v] + len < d[to]) {
q.erase({d[to], to});
d[to] = d[v] + len;
p[to] = v;
q.insert({d[to], to});
}
}
}
}