2017-08-03 21:56:45 +05:30
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/* Stack!!
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* A stack is exactly what it sounds like. An element gets added to the top of
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* the stack and only the element on the top may be removed. This is an example
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* of an array implementation of a Stack. So an element can only be added/removed
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* from the end of the array.
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*/
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// Functions: push, pop, peek, view, length
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2020-05-03 09:05:12 +02:00
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// Creates a stack constructor
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2021-05-21 11:16:11 +05:30
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const Stack = (function () {
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2020-05-03 09:05:12 +02:00
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function Stack () {
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// The top of the Stack
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this.top = 0
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// The array representation of the stack
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2020-05-03 21:26:52 -03:00
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this.stack = []
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2018-03-30 15:53:17 +02:00
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}
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2017-08-03 21:56:45 +05:30
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2020-05-03 09:05:12 +02:00
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// Adds a value onto the end of the stack
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2018-03-30 15:53:17 +02:00
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Stack.prototype.push = function (value) {
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2020-05-03 09:05:12 +02:00
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this.stack[this.top] = value
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this.top++
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}
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2017-08-03 21:56:45 +05:30
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2020-05-03 09:05:12 +02:00
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// Removes and returns the value at the end of the stack
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2018-03-30 15:53:17 +02:00
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Stack.prototype.pop = function () {
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if (this.top === 0) {
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2020-05-03 09:05:12 +02:00
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return 'Stack is Empty'
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2017-08-03 21:56:45 +05:30
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}
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2020-05-03 09:05:12 +02:00
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this.top--
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2021-05-21 11:16:11 +05:30
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const result = this.stack[this.top]
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2020-07-24 09:38:56 +05:30
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this.stack = this.stack.splice(0, this.top)
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2020-05-03 09:05:12 +02:00
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return result
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}
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2017-08-03 21:56:45 +05:30
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2020-05-03 09:05:12 +02:00
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// Returns the size of the stack
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2018-03-30 15:53:17 +02:00
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Stack.prototype.size = function () {
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2020-05-03 09:05:12 +02:00
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return this.top
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}
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2017-08-03 21:56:45 +05:30
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2020-05-03 09:05:12 +02:00
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// Returns the value at the end of the stack
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2018-03-30 15:53:17 +02:00
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Stack.prototype.peek = function () {
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2020-05-03 09:05:12 +02:00
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return this.stack[this.top - 1]
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2017-08-03 21:56:45 +05:30
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}
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2020-05-03 09:05:12 +02:00
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// To see all the elements in the stack
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2021-10-10 16:11:06 +02:00
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Stack.prototype.view = function (output = value => console.log(value)) {
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for (let i = 0; i < this.top; i++) {
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output(this.stack[i])
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}
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2020-05-03 09:05:12 +02:00
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}
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2018-03-30 15:53:17 +02:00
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2020-05-03 09:05:12 +02:00
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return Stack
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}())
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2017-08-03 21:56:45 +05:30
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2021-10-10 16:11:06 +02:00
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export { Stack }
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