JavaScript6/Data-Structures/Queue/QueueUsing2Stacks.js at master · stophobia/JavaScript6 · GitHub

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// implementation of Queue using 2 stacks

// contribution made by hamza chabchoub for a university project

class Queue {

constructor() {

this.inputStack = []

this.outputStack = []

}

// Push item into the inputstack

enqueue(item) {

this.inputStack.push(item)

}

dequeue() {

// push all items to outputstack

this.outputStack = []

while (this.inputStack.length > 0) {

this.outputStack.push(this.inputStack.pop())

}

// return the top element of the outputstack if any

if (this.outputStack.length > 0) {

const top = this.outputStack.pop()

// repush all the items to the inputstack

this.inputStack = []

while (this.outputStack.length > 0) {

this.inputStack.push(this.outputStack.pop())

}

return top

}

export { Queue }

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