Can anyone explain output of the algorithm When input in the queue is contain these numbers as written 100,153,127,143,162 ?

Question

When input is 100,153,127,143,162
Algorithm CHANGE (Queue)
{
queue size = queue count (queue)
count = 0
loop (count< queue size)
{
dequeue (queue, queue data)
if (queue data NOT less than 145)
{
enqueue (queue, queue data)
dequeue (queue, queue data)
}
else
enqueue (queue, queue data)
count=count + 1
}
return
}

Answer is 153 can anyone explain how?

Answer 1

Well, let's handtrace what happens. Since there are five elements inside the queue, there will be five iterations of the loop.
At the beginning of each iteration, the first element at the front is removed.

Queue: 162 143 127 153 100

Iteration 1:
162 is at the front -> 162 > 145 -> if-case:
162 is added to the back, 143 (current front element, since 162 was removed) is removed

Queue: 127 153 100 162

Iteration 2:
127 is at the front -> 127 < 145 -> else-case:
127 is added to the back

Queue: 153 100 162 127

Iteration 3:
153 is at the front -> 153 > 145 -> if-case:
153 is added to the back, and 100 is removed

Queue: 162 127 153

Iteration 4:
162 is at the front -> 162 > 145 -> if-case:
162 is added to the back, and 127 is removed

Queue: 153 162

Iteration 5:
153 is at the front -> 153 > 145 -> if-case:
153 is added to the back, 162 is removed

Queue: 153

Now the loop terminates, and the queue results in only containing 153. Here is a sample program in C++:
https://code.sololearn.com/c435C0Uc13In/?ref=app

Answer 2

Shadow thanks for the help it's pretty much clearer and good explanation it help me to understand thanks an heaps 👍