Question

Write a function called

dequeue_element(queue, i)

that takes a queue called queue and an index of an element in the queue, i. This function should get the element at index i of the queue and dequeue it but leave all of the other elements in the original order. The function should then return the dequeued value

For example, if queue = [A, B, C, D, E, F, G] and the function is called as:

dequeue_element(queue, 2)

Once the function is complete, queue = [A, B, D, E, F, G] and the function returns C. If i is out of range, raise a Exception. To get full credit, this function should not use any additional list-based data structures (stacks, lists, dequeues, strings etc).

in python

Answer 1

CODE :

Explanation is avaliable in the comments

def dequeue_element(queue,index):
  
queue_len=len(queue) # length of the queue
  
if index < 0:
raise Exception("Given Index is out of range") # raising exception if index is out of range.
  
if index > queue_len:
raise Exception("Given Index is out of range") # raising exception if index is out of range.
  
else:
  
# avoiding slicing solution as it is creating another additonal list.
# only way is to traverse O(N).
  
for i in range(0,queue_len): # traversing till the index found.
if index == i:
break;
  
queue_element_removed = queue[i] #element which is to be removed
  
# relocating elements
  
for j in range(i+1,queue_len):
queue[j-1]=queue[j]
  
queue.pop() # removes last element
  
return queue

queue = ['A', 'B' , 'C', 'D' , 'E', 'F', 'G']

index=2

# Function calling

print(dequeue_element(queue,index))

print(dequeue_element(queue,1))
print(dequeue_element(queue,5))
print(dequeue_element(queue,0))

Output :