Merge pull request neetcode-gh#2624 from aadil42/patch-66

Create 1268-search-suggestions-system.js

javascript/1268-search-suggestions-system.js

@@ -0,0 +1,157 @@
+/**
+ * Binary Search
+ * 
+ * Time O(n*log(n) + m*n) | Space O(m)
+ * https://leetcode.com/problems/search-suggestions-system/description/
+ * @param {string[]} products
+ * @param {string} searchWord
+ * @return {string[][]}
+ */
+var suggestedProducts = function(products, searchWord) {
+
+ products.sort((product1, product2) => {
+ if(product1 < product2) {
+ return -1;
+ }
+ if(product2 < product1) {
+ return 1;
+ }
+ if(product1 === product2) {
+ return 0;
+ }
+ });
+
+ const result = [];
+ let left = 0;
+ let right = products.length - 1;
+ for(let i = 0; i < searchWord.length; i++) {
+ let char = searchWord[i];
+
+ while(left <= right && (products[left].length - 1 < i || products[left][i] !== char)) {
+ left++;
+ }
+ while(left <= right && (products[right].length - 1 < i || products[right][i] !== char)) {
+ right--;
+ }
+
+ const subResult = [];
+ const len = Math.min(right - left + 1, 3);
+ for(let j = 0; j < len; j++) {
+ subResult.push(products[left+j]);
+ }
+ result.push(subResult);
+ }
+
+ return result;
+};
+
+/**
+ * DFS - Trie
+ * Time O(N * M) | Space O(N)
+ * https://leetcode.com/problems/search-suggestions-system/
+ * @param {string[]} products
+ * @param {string} searchWord
+ * @return {string[][]}
+ */
+var suggestedProducts1 = (products, searchWord) => new Trie()
+ .buildTrie(products)
+ .searchWord(searchWord);
+
+class Node {
+ constructor () {
+ this.children = new Map();
+ this.isWord = false;
+ }
+};
+
+class Trie {
+ constructor () {
+ this.root = new Node();
+ }
+
+ buildTrie (products) {
+ for (const word of products) {
+ this.insert(word);
+ }
+
+ return this;
+ }
+
+ insert (word, { root: node } = this) { 
+ for (const char of word.split('')) {
+ const child = (node.children.get(char) ?? new Node());
+
+ node.children.set(char, child);
+
+ node = child;
+ }
+
+ node.isWord = true;
+ }
+
+ searchWord (searchWord, buffer = [], suggestions = []) {
+ for (const char of searchWord.split('')) {
+ const prefix = this.getPrefix(buffer, char);
+ const words = this.getSuggestions(prefix);
+
+ suggestions.push(words);
+ }
+
+ return suggestions;
+ }
+
+ getPrefix (buffer, char) {
+ buffer.push(char);
+
+ return buffer.join('');
+ }
+
+ getSuggestions (prefix, words = []) {
+ const node = this.getPrefixNode(prefix);
+
+ const isInvalidPrefix = (node === null);
+ if (isInvalidPrefix) return words
+
+ return this.search(node, prefix, words);
+ }
+
+ getPrefixNode (prefix, { root: node } = this) {
+ for (const char of prefix.split('')) {
+ const child = (node.children.get(char) ?? null);
+
+ const isLeafNode = (child === null);
+ if (isLeafNode) return null;
+
+ node = child;
+ }
+
+ return node;
+ }
+
+ search (node, word, words) {
+ const isBaseCase = (words.length === 3);
+ if (isBaseCase) return words;
+
+ if (node.isWord) words.push(word);
+
+ return this.dfs(node, word, words);
+ }
+
+ dfs (node, word, words) {
+ for (const char of this.getChars()) {
+ const child = (node.children.get(char) ?? null);
+
+ const isLeafNode = (child === null);
+ if (isLeafNode) continue;
+
+ this.search(child, (word + char), words);
+ }
+
+ return words;
+ }
+
+ getChars () {
+ return new Array(26).fill()
+ .map((_, index) => String.fromCharCode((index + 97)));
+ }
+};