Implement Queue Using Stacks

Objective: We know that Queue is FIFO (First-in-First-Out) and Stack is LIFO ( Last-in-First-Out).

Here our objective is to implement queue using stacks.

Approach:

• Take 2 Stacks, stack1 and stack2.
• stack1 will be used a back of the Queue and stack2 will be used as front of the Queue.
• Push() operation will be done on stack1, and peek() and pop() operations will be done on stack2.
• When peek() and pop() are called, check is stack2 is empty, if yes then move all the elements from stack1 and push them into stack2.

Example:

Run This Code

Code:

Output:

POP from Queue 10

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