feat: implement-trie-prefix-tree

Author: soobing

implement-trie-prefix-tree/soobing3.ts

@@ -0,0 +1,52 @@
+class TrieNode {
+  children: Map<string, TrieNode>;
+  isEnd: boolean;
+  constructor() {
+      this.children = new Map();
+      this.isEnd = false
+  }
+}
+class Trie {
+  root: TrieNode;
+
+  constructor() {
+      this.root = new TrieNode();
+  }
+
+  insert(word: string): void {
+      let node = this.root;
+      for(const ch of word) {
+          if(!node.children.has(ch)) {
+              node.children.set(ch, new TrieNode());
+          }
+          node = node.children.get(ch)!
+      }
+      node.isEnd = true;
+  }
+
+  search(word: string): boolean {
+      let node = this.root;
+      for(const ch of word) {
+          if(!node.children.has(ch)) return false;
+          node = node.children.get(ch)!;
+      }
+      return node.isEnd;
+  }
+
+  startsWith(prefix: string): boolean {
+      let node = this.root;
+      for(const ch of prefix) {
+          if(!node.children.has(ch)) return false;
+          node = node.children.get(ch)!;
+      }
+      return true;
+  }
+}
+
+/**
+* Your Trie object will be instantiated and called as such:
+* var obj = new Trie()
+* obj.insert(word)
+* var param_2 = obj.search(word)
+* var param_3 = obj.startsWith(prefix)
+*/