Question

I. In the example of recycling the elements of a list in O1) time, which situation holds? A. Both lists are circular B. Both ists are not circular C. The list to be recycled is circular, the garbage list is not D. The garbage list is circular, the list to be recycled is not 2. What is the worst-case time to perform MINIMUML) for a sorted, doubly-linked list with nodes? A.6(1) B. Θ(log n) C. Θ(n) D. Θ(nlogn) . Which binary tree traversal corresponds to the following recursive code? void traverse (noderef x) if (x==null) retur / process x here traverse(x.left) traverse(x.right) A. norder B. postorder C. preorder D. search for key x 4. Suppose that only numbers in 100 appear as keys in a binary search tree. While searching for 50, which of the following sequences of keys could not be examined? A. 10, 30, 70, 60, 30 C. 1, 100, 20, T0, S0 B. 100, 20, 80, 30, 50 D. 10, 40, 70, 30, 50 5. What does counting sort count? A. the number of bytes in the input array B. the number of occurences for each possible key value C. the number of different input values that have oecured D. the maximum length among al the strings being sorted 6. Which of the following is not true regarding dynamic programming? A. It is a form of divide-and-conquer C. A cost function must be defined B. It is a form of exhaustive search D. The backtrace may be hased on recomputing the cost function . The time to extract the LCS for sequences of lengthsand ) atter filling in the dynamic programming matrix is in: C. Θ(n logn) D. emn) 8. The qucue for breadth-first rat-in-a-maze stores A. all maze positions that have walls B. maze positions that must be in the final path C. maze positions that have been reached D e current path being explored 9. For which of the following sorts does the decision tree model not apply? I0. Given a pointer to a node, the worst-case time to delete the node from a singly-linked list withn nodes in ascending order 11. Memoization is associated with which technique? A. Insertion B. LSD Radix Sort C. MERGE-SORT D. QUICKSORT C. Θ(n loge) A. top-down dynamic programming C. greedy methods B. circular lists D. bottom-up dynamic programming 12. If POP is implemented as return stackSPl, then PUSH of element X is implemented as A. return stack[SP++] B. stack[SP++]=X C. stack-SPJ-X D. stack[++SP]-X 13. The cost function for the optimal matrix multiplication problem is isk<j isk<j C. ct İskej 14. The worst-case number of comparisons for finding the kth largest of n keys using PARTITION is in which asymptotic set? A Θ(log n) B. Θ(n) c Θ(nlogn) 15. Suppose a (singly) linked list is used to implement a queue. Which of the following is true? A. The head points to the first element and the tail points to the last element, B. The tail points to the fist element and the head points to the last element. . Like a cular queue, the maximum number of items is determined at initialization D. One node is always wasted

can anyone provide answers with explaination ? thanks a lot

Answer 1

1. Answer: C Explanation: The list to be recycled is circular because repeatedly go around the list and it takes O(1) for recycling the elements of a list the garbage list is not. Therefore, answer is option C that is the list to be recycled is circular, the garbage list is not. 2. Answer: A Explanation: As per the question, list is a sorted and doubly linked list, that means starting node of the list contains the minimum value. Time taken to access the first node in the doubly linked list is O(1). Therefore, the answer is option A that is the worst-case time to perform MINIMUM(L) for an ordered, doubly linked list with n nodes is 0(1). 3. Answer: C Explanation: Preorder traverse : root – left-right. In order traverse : left-root - right. Post order traverse : left-right-root. Therefore, the answer is option C that is preorder traverse because given function first process noderef x and then it traverses left tree and then right subtree.

4. Answer: D . Explanation: find 50 in BST: In first option 10 is root node, our key is greater than 10 so we go for right BST. Next node is 30 - 70 -60 50 respectively. In second option 100 is root node, we go for left BST i.e. 20 80 →3050 respectively. In third option 1 is root node, we go for right BST i.e. 100 - 2070 50 respectively In fourth option 10 is root node, we go for right BST i.e. 40 - 70 next key is 30 we can't go for 30 after 70 because we are already in right BST of 40 our key will be surely in right BST of 40. This option is incorrect. So, option (D) is correct. . -+ 5. Answer: B Explanation: Counting sort counts the number of keys whose key values are same. Therefore, the answer is option B that is the number of occurrences for each key value. 6. Answer: A Explanation: In divide and conquer, the problem is divided into smaller non-overlapping subproblems and an optimal solution for each of the subproblems is found. Therefore, the answer is option A that is a form of divide and conquer.

1. Answer: D Explanation: Whenever the function Ics(m, n) with the same argument m and n are called again, do not perform any further recursive call and return matrix[m-1][n-1) as the previous computation of the lcs(m, n) has already been stored in matrix [m-1][n-1], hence reducing the recursive calls that happen more than once. Hence, answer is option that is (mn). 8. Answer: D Explanation: Breadth-first is easily implementing by having a queue of paths to search. Hence, answer is the option that is the current path being explored. 9. Answer: B Explanation: Decision tree model does not apply to counting sort, radix sort, bucket sort. Hence, the correct answer is option B that is LSD Radix Sort. 10. Answer: A Explanation: Worst case complexity for deleting a node from singly linked list is O(1). Hence, the correct answer is option A that is O(1).

11. Answer: A Explanation: In Memoization, you store the expensive function calls in a cache and call back from there if exist when needed again. This is a top-down approach, and it has extensive recursive calls. Hence, the correct answer is option A that is top-down dynamic programming. 12. Answer: B Explanation: As per the question, to pop element from the stack, first decreased stack pointer (SP) by one that means stack pointer points any empty location initially and then pop the top of the stack. So, to push X into stack, first need to insert X into top of the stack and then increment SP by one. Hence, the correct answer is option A that is stack[SP++] = X. 13. Answer: C Explanation: To compute the minimum cost of Cli, j) using below function. C(ij) = min{C(i,k) + C(k +1,j) + Pi-1PxP;} Hence, the correct answer is option C. 14. Answer: B Explanation: The expected number of comparisons for finding the kth largest of n keys using PARTITION is in O(n). Hence, the correct answer is option B.

15. Answer: A Explanation: For queue, inserting elements at end of the list and removing list from front of the list, so head needs to point first element and the tails points to last element. Hence, the correct answer is option A.