26 lines
644 B
JavaScript
26 lines
644 B
JavaScript
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// https://www.freecodecamp.org/learn/coding-interview-prep/data-structures/reverse-a-doubly-linked-list
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var Node = function (data, prev) {
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this.data = data;
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this.prev = prev;
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this.next = null;
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};
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var DoublyLinkedList = function () {
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this.head = null;
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this.tail = null;
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// Only change code below this line
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this.reverse = () => {
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const newTail = this.head;
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let node = this.head;
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while (node !== null) {
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const newPrev = node.next;
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node.next = node.prev;
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node.prev = newPrev;
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node = newPrev;
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}
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this.head = this.tail;
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this.tail = newTail;
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};
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// Only change code above this line
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};
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