design add and search words data structure solution

Author: hyer0705

design-add-and-search-words-data-structure/hyer0705.ts

@@ -0,0 +1,68 @@
+class TNode {
+  isEndOf: boolean;
+  children: Map<string, TNode>;
+
+  constructor() {
+    this.isEndOf = false;
+    this.children = new Map<string, TNode>();
+  }
+}
+
+class WordDictionary {
+  private root: TNode;
+
+  constructor() {
+    this.root = new TNode();
+  }
+
+  addWord(word: string): void {
+    let current = this.root;
+
+    for (const ch of word) {
+      if (!current.children.has(ch)) {
+        current.children.set(ch, new TNode());
+      }
+
+      current = current.children.get(ch)!;
+    }
+
+    current.isEndOf = true;
+  }
+
+  search(word: string): boolean {
+    const find = (node: TNode, index: number): boolean => {
+      if (index === word.length) {
+        if (node.isEndOf) return true;
+        return false;
+      }
+
+      const currentCh = word[index];
+
+      if (currentCh === ".") {
+        for (const [ch, child] of node.children) {
+          if (find(child, index + 1)) return true;
+        }
+
+        return false;
+      } else {
+        const child = node.children.get(currentCh);
+        if (child) {
+          return find(child, index + 1);
+        }
+
+        return false;
+      }
+
+      return false;
+    };
+
+    return find(this.root, 0);
+  }
+}
+
+/**
+ * Your WordDictionary object will be instantiated and called as such:
+ * var obj = new WordDictionary()
+ * obj.addWord(word)
+ * var param_2 = obj.search(word)
+ */