4. Dijkstra's

// Adjacency List
vector<vector<pair<int,int>>> adj(n + 1);

// Build Graph
for (auto &edge : times) {  
	int u = edge[0];  
	int v = edge[1];  
	int wt = edge[2];  
  
	adj[u].push_back({v, wt});  
}

// Min Heap
priority_queue<
    pair<int,int>,
    vector<pair<int,int>>,
    greater<pair<int,int>>
> pq;

// Distance Array
vector<int> dist(V, INT_MAX);

dist[src] = 0;
// parent[src] = src; // If you also want the path

pq.push({0, src});

while (!pq.empty()) {

    auto [distance, node] = pq.top();
    pq.pop();

	// Skip outdated entries
    if (distance > dist[node])
        continue;
	
	// Explore neighbors
    for (auto [neighbor, weight] : adj[node]) {
		
		// Relax the edge
        if (dist[node] + weight < dist[neighbor]) {

            dist[neighbor] = dist[node] + weight;

			// Store parent  
		 	// parent[neighbor] = node;
			
            pq.push({dist[neighbor], neighbor});
        }
    }
}
// dist[i] contains shortest distance from src to i

To get the path

vector<int> path;

if (dist[dest] == INT_MAX) {
    cout << "No Path";
}
else {
    int node = dest;

    while (node != parent[node]) {
        path.push_back(node);
        node = parent[node];
    }
    
    path.push_back(src);
    reverse(path.begin(), path.end());
}