DSA · Theory

Implementation of Queue using Stacks

Theory

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Implementation of Queue using Stacks

Implementation of Queue using Stacks is a DSA topic. In plain words you use it for print jobs in a lab printer. Don’t start with a slogan — start with that picture.

Smallest example: enqueue / dequeue FIFO. Type it, run it, and say what you see. If you can do that from memory, you know Implementation of Queue using Stacks.

From the example next to this theory — Implementation of Queue using Stacks — queue is FIFO.

Trap — confusing front and rear. Fix that before you talk about advanced DSA.

Viva — what is Implementation of Queue using Stacks? Then show enqueue / dequeue FIFO. Then name the trap.

Diagram

  front → [A][B][C] ← rear
  out ↑         ↑ in
       FIFO

Exam tip

What is Implementation of Queue using Stacks? Show this: enqueue / dequeue FIFO. Trap: confusing front and rear.

Example

from collections import deque

q = deque()
q.append(10)      # enqueue
q.append(20)
print(q.popleft())  # 10
print(list(q))

Implementation of Queue using Stacks — queue is FIFO. deque.popleft() is O(1).

Short notes

DefImplementation of Queue using Stacks — print jobs in a lab printer.
Ruleenqueue / dequeue FIFO
Trapconfusing front and rear
Usea lab printer

DSA · Theory

Implementation of Queue using Stacks

← All stacks

Theory

138/810

Implementation of Queue using Stacks

Implementation of Queue using Stacks is a DSA topic. In plain words you use it for print jobs in a lab printer. Don’t start with a slogan — start with that picture.

Smallest example: enqueue / dequeue FIFO. Type it, run it, and say what you see. If you can do that from memory, you know Implementation of Queue using Stacks.

From the example next to this theory — Implementation of Queue using Stacks — queue is FIFO.

Trap — confusing front and rear. Fix that before you talk about advanced DSA.

Viva — what is Implementation of Queue using Stacks? Then show enqueue / dequeue FIFO. Then name the trap.

Diagram

  front → [A][B][C] ← rear
  out ↑         ↑ in
       FIFO

Exam tip

What is Implementation of Queue using Stacks? Show this: enqueue / dequeue FIFO. Trap: confusing front and rear.

Example

from collections import deque

q = deque()
q.append(10)      # enqueue
q.append(20)
print(q.popleft())  # 10
print(list(q))

Implementation of Queue using Stacks — queue is FIFO. deque.popleft() is O(1).

Short notes

DefImplementation of Queue using Stacks — print jobs in a lab printer.
Ruleenqueue / dequeue FIFO
Trapconfusing front and rear
Usea lab printer

Implementation of Queue using Stacks

Example

Short notes

Questions

Implementation of Queue using Stacks

Example

Short notes

Questions