Implement Queue using Stacks Problem

Implement Queue using Stacks Problem — ExecCode Easy DSA Practice

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Problem description

Implement a first in first out (FIFO) queue using only two stacks. The implemented queue should support all the functions of a normal queue (push, peek, pop, and empty). Implement the MyQueue class: - MyQueue() Initializes the object. - void push(int x) Pushes element x to the back of the queue. - int pop() Removes the element from the front of the queue and returns it. - int peek() Returns the element at the front without removing it. - boolean empty() Returns true if the queue is empty, false otherwise.

Examples

Input {"ops": ["push", "push", "push", "peek", "push", "pop", "pop", "peek", "empty"], "vals": [1, 2, 3, 0, 4, 0, 0, 0, 0]}; Output [1, 1, 2, 3, False]. Input {"ops": ["push", "push", "peek", "pop", "empty"], "vals": [1, 2, 0, 0, 0]}; Output [1, 1, False]. Input {"ops": ["push", "pop", "empty"], "vals": [5, 0, 0]}; Output [5, True]

Constraints

1 ≤ x ≤ 9 At most 100 calls will be made to push, pop, peek, and empty. All the calls to pop and peek are valid.

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