118 lines
2.5 KiB
JavaScript
118 lines
2.5 KiB
JavaScript
const root = Symbol("root");
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class BinarySearchTreeNode {
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constructor (value) {
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this.value = value;
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this.left = null;
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this.right = null;
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}
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}
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class BinarySearchTree {
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constructor () {
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this[root] = null;
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}
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add (value) {
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const node = new BinarySearchTreeNode(value);
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let current = null;
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// No items in tree
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if (this[root] === null) {
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this[root] = node;
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} else {
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current = this[root];
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while (true) {
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if (value < current.value) {
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// If there's no left, insert
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if (current.left === null) {
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current.left = node;
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break;
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}
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current = current.left;
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} else if (value > current.value) {
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if (current.right === null) {
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current.right = node;
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break;
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}
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current = current.right;
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} else {
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break;
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}
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}
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}
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}
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contains (value) {
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let found = false;
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let current = this[root];
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while ( ! found && current !== null) {
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if (value < current.value) {
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current = current.left;
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} else if (value > current.value) {
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current = current.right;
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} else if (value === current.value) {
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found = true;
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}
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}
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return found;
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}
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remove (value) {
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}
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size () {
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let length = 0;
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this.traverse(() => {
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length++;
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});
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return length;
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}
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traverse (process) {
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const inOrder = (node) => {
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if ( ! node) {
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return;
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}
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// traverse the left subtree
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if (node.left !== null) {
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inOrder(node.left);
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}
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// handle the current node
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process.call(this, node);
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// traverse the right subtree
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if (node.right !== null) {
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inOrder(node.right);
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}
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};
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// start with the root
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inOrder(this[root]);
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}
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toArray () {
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let result = [];
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this.traverse((node) => {
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result.push(node.value);
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});
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return result;
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}
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toString () {
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return this.toArray().toString();
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}
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} |