@@ -0,0 +1,9 @@
+// 测试字典树
+const Trie = require('./Trie');
+var t = new Trie();
+t.add('happy');
+t.add('birthday');
+t.add('cat');
+t.add('catch');
+console.log(t.getSize());
+console.log(t.isPrefix('ca'));
@@ -0,0 +1,58 @@
+// 定义节点
+class Node {
+    constructor(isWord=false) {
+        this.isWord = isWord;
+        this.next = new Map();
+    }
+}
+// 字典树
+module.exports = class Trie{
+    constructor() {
+        this.root = new Node();
+        this.size = 0;
+    }
+    // 获取Trie中存储的单词数量
+    getSize() {
+        return this.size;
+    }
+    // 向Trie中添加一个新的单词word
+    add(word) {
+        // 非递归写法，字符串拆成字符
+        let cur = this.root;
+        for(let i = 0;i < word.length; i++) {
+            let c = word.charAt(i);
+            if(cur.next.get(c) === undefined) {
+                cur.next.set(c, new Node());
+            }
+            cur = cur.next.get(c); // 走到下一个节点
+        }
+        // 这个节点以前不表示单词结尾
+        if(!cur.isWord) {
+            cur.isWord = true;
+            this.size++;
+        }
+    }
+    // 查询单词word是否在Trie中
+    contains(word) {
+        let cur = root;
+        for(let i = 0;i < word.length; i++) {
+            let c = wrod.charAt(i);
+            if(cur.next.get(c) === null)
+                return false;
+            cur = cur.next.get(c);
+        }
+        // 比如trie中有panda，查pan。查到节点，但是并没有这个单词
+        return cur.isWord;
+    }
+    // 前缀查询
+    isPrefix(prefix) {
+        let cur = this.root;
+        for(let i = 0; i < prefix.length; i++) {
+            let c = prefix.charAt(i);
+            if(cur.next.get(c) === undefined)
+                return false;
+            cur = cur.next.get(c);
+        }
+        return true;
+    }
+}
@@ -44,6 +44,11 @@
 - [线段树I](./JavaScript/SegmentTree/SegmentTree.js)
 - [线段树II](./JavaScript/SegmentTree/SegmentTreeII.js)
 
+### 字典树:
+一种树型结构，用于字符串匹配
+
+- [字典树](./JavaScript/Trie/Trie.js)
+
 ### 图论：
 
 - [图的实现](./JavaScript/Graph/Graph.js)