✨ [211] FIRST TRIE!!!

Author: enkr1

211/my_solution.js

@@ -0,0 +1,151 @@
+class TrieNode {
+
+  constructor() {
+    const ALPHABET_LENGTH = 26;
+
+    this.isEndOfWord = false;
+    this.children = new Array(ALPHABET_LENGTH).fill(null)
+  }
+
+  getIdx(char) {
+    return char.charCodeAt() - "a".charCodeAt();
+  }
+}
+
+
+class WordDictionary {
+  constructor() {
+    this.root = new TrieNode();
+  }
+
+  /**
+   * @param {string} word
+   * @return {void}
+   */
+  addWord(word) {
+
+    let root = this.root;
+    for (let i = 0; i < word.length; i++) {
+      // console.log(word[i].charCodeAt() - "a".charCodeAt())
+      let idx = root.getIdx(word[i]);
+      if (null === root.children[idx]) root.children[idx] = new TrieNode();
+      root = root.children[idx];
+    }
+
+    root.isEndOfWord = true;
+    // console.log(this.root)
+    // console.log(this.root.children[3])
+    // console.log(this.root.children[3].children[0])
+    // console.log(this.root.children[3].children[0].children)
+  }
+
+  /**
+   * @param {string} word
+   * @return {boolean}
+   */
+  search(word) {
+    const dfs = (i, node) => {
+      console.log(`word:${word}, i:${i}, l:${word.length}`)
+      if (node.isEndOfWord && i === word.length) return true;
+      if (word[i] === undefined) return false;
+      let idx = node.getIdx(word[i]), nextI = i + 1;
+
+      console.log(`node.getIdx(word[i]): ${node.getIdx(word[i])}`)
+
+      if (idx < 0) {
+        console.log("word[i]")
+        console.log(word[i])
+        // console.log(node.children)
+
+        for (let possibleChild of node.children) {
+          if (possibleChild === null) continue;
+
+          console.log("possibleChild")
+          console.log(possibleChild)
+          if (dfs(nextI, possibleChild)) return true;
+        }
+        console.log("??????")
+        // all null
+        return false;
+      } else {
+        let child = node.children[idx];
+        console.log("child")
+        console.log(child)
+
+        if (null === child) return false;
+
+        return dfs(nextI, child);
+      }
+    }
+
+    return dfs(0, this.root);
+  }
+};
+
+// let tn = new TrieNode();
+// tn.insert("dad")
+// tn.insert("daddy")
+// console.log(tn.children[3])
+// console.log(tn.children[3].children[0])
+let wd = new WordDictionary();
+
+wd.addWord("at")
+wd.addWord("and")
+wd.addWord("an")
+wd.addWord("add")
+console.log(wd.search("a"))
+console.log(wd.search(".at"))
+wd.addWord("bat")
+console.log(wd.search(".at"))
+
+// for (word of [".at", "an.", "a.d.", "b.", "a.d", "."]) {
+//   console.log(wd.search(word))
+//
+//   console.log("word")
+//   console.log(word)
+// }
+// wd.addWord("a")
+// wd.addWord("ab")
+// console.log(wd.root.children)
+
+
+
+// console.log(wd.search("a"))
+// console.log(wd.search("a."))
+// console.log(wd.search("ab"))
+// console.log(wd.search(".a"))
+// console.log(wd.search(".b"))
+// console.log(wd.search("ab."))
+// console.log(wd.search("."))
+// console.log(wd.search(".."))
+
+// wd.addWord("a")
+// wd.addWord("a")
+
+// wd.addWord("dad")
+// wd.addWord("mad")
+// wd.addWord("pad")
+
+// console.log("Result")
+// console.log(wd.search(".")) // t
+// console.log(wd.search("a")) // t
+// console.log(wd.search("aa"))
+// console.log(wd.search("a")) // t
+// console.log(wd.search(".a"))
+// console.log(wd.search("a."))
+// console.log(wd.search("a"))
+
+// [
+//   "WordDictionary",
+//   "addWord", "addWord", "addWord", "addWord",
+//   "search", "search",
+//   "addWord",
+//   "search", "search", "search", "search", "search", "search"
+// ]
+// [
+//   [],
+//   ["at"], ["and"], ["an"], ["add"],
+//   ["a"], [".at"],
+//   ["bat"],
+//   [".at"], ["an."], ["a.d."], ["b."], ["a.d"], ["."]
+// ]

211/solution.js

@@ -0,0 +1,65 @@
+class TrieNode {
+
+  constructor() {
+    const ALPHABET_LENGTH = 26;
+
+    this.isEndOfWord = false;
+    this.children = new Array(ALPHABET_LENGTH).fill(null)
+  }
+
+  getIdx(char) {
+    return char.charCodeAt() - "a".charCodeAt();
+  }
+}
+
+
+class WordDictionary {
+  constructor() {
+    this.root = new TrieNode();
+  }
+
+  /**
+   * @param {string} word
+   * @return {void}
+   */
+  addWord(word) {
+
+    let root = this.root;
+    for (let i = 0; i < word.length; i++) {
+      let idx = root.getIdx(word[i]);
+      if (null === root.children[idx]) root.children[idx] = new TrieNode();
+      root = root.children[idx];
+    }
+
+    root.isEndOfWord = true;
+  }
+
+  /**
+   * @param {string} word
+   * @return {boolean}
+   */
+  search(word) {
+    const dfs = (i, node) => {
+      if (node.isEndOfWord && i === word.length) return true;
+      if (word[i] === undefined) return false;
+      let idx = node.getIdx(word[i]), nextI = i + 1;
+
+      if (idx < 0) {
+        for (let possibleChild of node.children) {
+          if (possibleChild === null) continue;
+          if (dfs(nextI, possibleChild)) return true;
+        }
+
+        return false;
+      } else {
+        let child = node.children[idx];
+
+        if (null === child) return false;
+
+        return dfs(nextI, child);
+      }
+    }
+
+    return dfs(0, this.root);
+  }
+};

README.md

@@ -56,6 +56,7 @@
 - [200. Number of Islands](./200/)
 - [206. Reverse Linked List](./206/)
 - [207. Course Schedule](./207/)
+- [211. Design Add and Search Words Data Structure](./211/)
 - [213. House Robber II](./213/)
 - [217. Contains Duplicate](./217/)
 - [226. Invert Binary Tree](./226/)
@@ -146,7 +147,7 @@ Batch create:
 NOTE: JS IS HERE
 -->
 ```ssh
-chapter=230 && mkdir ./$chapter && touch ./$chapter/my_solution.js && touch ./$chapter/solution.js && alias x="node ./$chapter/my_solution.js"
+chapter=211 && mkdir ./$chapter && touch ./$chapter/my_solution.js && touch ./$chapter/solution.js && alias x="node ./$chapter/my_solution.js"
 ```
 > then you can use `x` for quick debug.