Question

Show what is written by following segments of code, given that element1, element2, and element3, are int variables, and queue is an object that fits the abstract description of a queue as given in Section 5.2. Assume that you can store and retrieve values of type int in queue. a. element1 = 1; element2 = 0; element 3 =4 queue.enqueue(element2); queue.enqueue(element1); queue.enqueue(element1 + element3); element 2 = queue.dequeue() queue.enqueue(element3 element3); queue.enqueue(element2); queue.enqueue(3); element1 = queue.dequeue(); System.out.pfintln(element1 + " " + element2 + "" + element3); while (!queue.isEmpty()) {element1 = queue.dequeue(); System.out .pnntln(element 1);}

Answer 1

Enqueue is an operation of inserting element to queue Dequeue is an operation of removing element from queue It works on the policy of FIFO, first in first out. So, if we insert element 1 and 2 to queue, enqueue(1), enqueue(2), queue will be like, 1 2, dequeue) will remove first inserted element so queue will be 2 (Not that 1 was inserted first so removed first) Initially element1-1; element2 0; element3 4 line description insert element2 to Q insert element1 to Q Q status 0 01 015 ueue.enqueue(element2 queue.enqueue(element1); ueue.enqueue(element1+ element3; insert element1element3 to Q element2 queue.dequeue0; Assign front (first element to element element2 0 and remove it from Q 15 15 16 15160 15160 3 element2 5 160 3 ueue.enqueue(element3element3); insert element3element3 to Q queue.enqueue(element2); insert element2 to Q insert 3 to Q Assign front (first element to element2 and remove it from ueue.engueue(3 element2 queue.dequeue() 1 System.out.println(elemet1+print element1 element2 element3 5 16 03 element2element3 while(!queue.isEmpty)) output 114 While there is element in queue Assign front (first element to element2 and remove it from Q), print element2 It will print like this element2 queue.dequeue(); System.out.println(element1); 16 0 3 So, output will be 114 16 0