Refactor BFS implementation for improved readability and safety

BfsCpp

@@ -1,58 +1,65 @@
+// } Driver Code Ends
 
- // } Driver Code Ends
-
+/*
+Algorithm: Breadth First Search (BFS)
+Time Complexity: O(V + E)
+Space Complexity: O(V)
+*/
 
 class Solution {
 public:
-	vector<int>bfsOfGraph(int V, vector<int> adj[]){
-	    vector<int> bfs; 
-	    vector<int> vis(V, 0); 
-	    queue<int> q; 
-	    q.push(0); 
-	    vis[0] = 1; 
-	    while(!q.empty()) {
-	        int node = q.front();
-	        q.pop(); 
-	        bfs.push_back(node); 
-
-	        for(auto it : adj[node]) {
-	            if(!vis[it]) {
-	                q.push(it); 
-	                vis[it] = 1; 
-	            }
-	        }
-	    }
-
-	    return bfs; 
-	}
+    vector<int> bfsOfGraph(int V, const vector<int> adj[]) {
+        vector<int> bfsTraversal;
+        vector<bool> visited(V, false);
+        queue<int> q;
+
+        // Start BFS from node 0
+        q.push(0);
+        visited[0] = true;
+
+        while (!q.empty()) {
+            int currentNode = q.front();
+            q.pop();
+            bfsTraversal.push_back(currentNode);
+
+            for (int neighbor : adj[currentNode]) {
+                if (!visited[neighbor]) {
+                    visited[neighbor] = true;
+                    q.push(neighbor);
+                }
+            }
+        }
+
+        return bfsTraversal;
+    }
 };
 
 // { Driver Code Starts.
-int main(){
-	int tc;
-	cin >> tc;
-	// for multiple graphs
-	while(tc--){
-		int V, E;
-    	cin >> V >> E;
-
-    	vector<int> adj[V];
-
-    	for(int i = 0; i < E; i++)
-    	{
-    		int u, v;
-    		cin >> u >> v;
-    		adj[u].push_back(v);
-    // 		adj[v].push_back(u); // uncomment this for undirected graoh 
-    	}
-        // string s1;
-        // cin>>s1;
+int main() {
+    int tc;
+    cin >> tc;
+
+    while (tc--) {
+        int V, E;
+        cin >> V >> E;
+
+        vector<int> adj[V];
+
+        for (int i = 0; i < E; i++) {
+            int u, v;
+            cin >> u >> v;
+            adj[u].push_back(v);
+            // adj[v].push_back(u); // Uncomment for undirected graph
+        }
+
         Solution obj;
-        vector<int>ans=obj.bfsOfGraph(V, adj);
-        for(int i=0;i<ans.size();i++){
-        	cout<<ans[i]<<" ";
+        vector<int> ans = obj.bfsOfGraph(V, adj);
+
+        for (int node : ans) {
+            cout << node << " ";
         }
-        cout<<endl;
-	}
-	return 0;
-}  // } Driver Code Ends
+        cout << endl;
+    }
+    return 0;
+}
+// } Driver Code Ends