Data structures worksheet with answers

In a tree, what are sibling nodes?

1. AA node and its parent
2. BNodes that share the same parent
3. CNodes at the same depth in different subtrees
4. DNodes that have no children

Which operation is slow in an array but fast at the head of a linked list?

1. AAccessing the 5th element
2. BFinding the length of a fixed array
3. CInserting at the beginning
4. DReading the last element by index

In a singly linked list, what does the next pointer of the last node contain?

1. AThe address of the first node
2. BNull (no node)
3. CThe address of the previous node
4. DThe number of nodes in the list

A node in a binary search tree has a right subtree. Where is its in-order successor?

1. AIts parent, always
2. BThe rightmost node of its left subtree
3. CThe leftmost node of its right subtree
4. DIts right child, always

Which collision resolution method stores colliding keys in a list at the same bucket?

1. AQuadratic probing
2. BLinear probing
3. CSeparate chaining
4. DDouble hashing

How long does it take to check whether the edge (u, v) exists using an adjacency matrix?

1. AO(log V)
2. BO(1)
3. CO(V)
4. DO(E)

How long does it take to search for an arbitrary key in a binary min-heap of n elements?

1. AO(n)
2. BO(log log n)
3. CO(1)
4. DO(log n)

Which pair of traversals always determines a unique binary tree with distinct keys?

1. ALevel-order alone
2. BPreorder and postorder
3. CPreorder and inorder
4. DPreorder alone