Permalink
Apr 11, 2021
Newer
100644
60 lines (51 sloc)
1.27 KB
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{
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class Node {
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constructor(value) {
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this.value = value;
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this.next = null;
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}
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}
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class Stack {
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constructor() {
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this.top = null;
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this.bottom = null;
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this.length = 0;
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}
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peek() {
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return this.top;
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}
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push(value) {
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const newNode = new Node(value);
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if (this.length === 0) {
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this.top = newNode;
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this.bottom = newNode;
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} else {
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const holdingPointer = this.top;
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this.top = newNode;
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this.top.next = holdingPointer;
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}
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this.length += 1;
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return this;
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}
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pop() {
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if (!this.top) {
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return null;
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}
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if (this.top === this.bottom) {
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this.bottom = null;
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}
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this.top = this.top.next;
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this.length -= 1;
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return this;
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}
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}
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const myStack = new Stack();
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console.log(`myStack.push("google"): `, myStack.push("google"));
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console.log(`myStack.push("udemy"): `, myStack.push("udemy"));
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console.log(`myStack.push("discord"): `, myStack.push("discord"));
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console.log(`myStack.peek(): `, myStack.peek());
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console.log(`myStack.pop(): `, myStack.pop());
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console.log(`myStack.pop(): `, myStack.pop());
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console.log(`myStack.pop(): `, myStack.pop());
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console.log(`myStack.peek(): `, myStack.peek());
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}