List of top Algorithms Questions on Graph traversals

Consider a complete binary tree with 7 nodes. Let \( A \) denote the set of first 3 elements obtained by performing Breadth-First Search (BFS) starting from the root. Let \( B \) denote the set of first 3 elements obtained by performing Depth-First Search (DFS) starting from the root. The value of \( |A - B| \) is \(\underline{\hspace{2cm}}\).

Consider the following directed graph: 
Which of the following is/are correct about the graph? 

An articulation point in a connected graph is a vertex such that removing the vertex and its incident edges disconnects the graph into two or more connected components. Let \(T\) be a DFS tree obtained by doing DFS in a connected undirected graph \(G\). Which of the following options is/are correct?