// 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 }