add 211-Design-Add-and-Search-Words-Data-Structure

Author: loczek

javascript/211-Design-Add-and-Search-Words-Data-Structure.js

@@ -0,0 +1,55 @@
+class TrieNode {
+  constructor() {
+    this.children = {};
+    this.endOfWord = false;
+  }
+}
+
+class WordDictionary {
+  constructor() {
+    this.root = new TrieNode();
+  }
+
+  addWord(word) {
+    let cur = this.root;
+
+    for (const c of word) {
+      if (!(c in cur.children)) {
+        cur.children[c] = new TrieNode();
+      }
+      cur = cur.children[c];
+    }
+    cur.endOfWord = true;
+  }
+
+  search(word) {
+    function dfs(j, root) {
+      let cur = root;
+
+      for (let i = j; i < word.length; i++) {
+        const c = word[i];
+
+        if (c === ".") {
+          for (const key in cur.children) {
+            if (Object.prototype.hasOwnProperty.call(cur.children, key)) {
+              const child = cur.children[key];
+
+              if (dfs(i + 1, child)) {
+                return true;
+              }
+            }
+          }
+          return false;
+        } else {
+          if (!(c in cur.children)) {
+            return false;
+          }
+          cur = cur.children[c];
+        }
+      }
+
+      return cur.endOfWord;
+    }
+    return dfs(0, this.root);
+  }
+}