feat: add js solution to lc ploblem: no.297

Author: lo0b0o

solution/0200-0299/0297.Serialize and Deserialize Binary Tree/README.md

@@ -74,6 +74,65 @@
 
 ```
 
+### **JavaScript**
+
+```js
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val) {
+ *     this.val = val;
+ *     this.left = this.right = null;
+ * }
+ */
+
+/**
+ * Encodes a tree to a single string.
+ *
+ * @param {TreeNode} root
+ * @return {string}
+ */
+var serialize = function (root) {
+    let data = [];
+    let serializeRec = function (root) {
+        if (!root) {
+            data.push(1001);
+            return null;
+        }
+        data.push(root.val);
+
+        serializeRec(root.left);
+        serializeRec(root.right);
+    }
+    serializeRec(root);
+    return data;
+};
+
+/**
+ * Decodes your encoded data to tree.
+ *
+ * @param {string} data
+ * @return {TreeNode}
+ */
+var deserialize = function (data) {
+    if (!data) {
+        return null;
+    }
+    let curVal = data.shift();
+    if (curVal == 1001) {
+        return null;
+    }
+    let node = new TreeNode(curVal);
+    node.left = deserialize(data);
+    node.right = deserialize(data);
+    return node;
+};
+
+/**
+ * Your functions will be called as such:
+ * deserialize(serialize(root));
+ */
+```
+
 ### **...**
 
 ```

solution/0200-0299/0297.Serialize and Deserialize Binary Tree/README_EN.md

@@ -64,6 +64,65 @@
 
 ```
 
+### **JavaScript**
+
+```js
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val) {
+ *     this.val = val;
+ *     this.left = this.right = null;
+ * }
+ */
+
+/**
+ * Encodes a tree to a single string.
+ *
+ * @param {TreeNode} root
+ * @return {string}
+ */
+var serialize = function (root) {
+    let data = [];
+    let serializeRec = function (root) {
+        if (!root) {
+            data.push(1001);
+            return null;
+        }
+        data.push(root.val);
+
+        serializeRec(root.left);
+        serializeRec(root.right);
+    }
+    serializeRec(root);
+    return data;
+};
+
+/**
+ * Decodes your encoded data to tree.
+ *
+ * @param {string} data
+ * @return {TreeNode}
+ */
+var deserialize = function (data) {
+    if (!data) {
+        return null;
+    }
+    let curVal = data.shift();
+    if (curVal == 1001) {
+        return null;
+    }
+    let node = new TreeNode(curVal);
+    node.left = deserialize(data);
+    node.right = deserialize(data);
+    return node;
+};
+
+/**
+ * Your functions will be called as such:
+ * deserialize(serialize(root));
+ */
+```
+
 ### **...**
 
 ```

solution/0200-0299/0297.Serialize and Deserialize Binary Tree/Solution.js

@@ -0,0 +1,54 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val) {
+ *     this.val = val;
+ *     this.left = this.right = null;
+ * }
+ */
+
+/**
+ * Encodes a tree to a single string.
+ *
+ * @param {TreeNode} root
+ * @return {string}
+ */
+var serialize = function (root) {
+    let data = [];
+    let serializeRec = function (root) {
+        if (!root) {
+            data.push(1001);
+            return null;
+        }
+        data.push(root.val);
+
+        serializeRec(root.left);
+        serializeRec(root.right);
+    }
+    serializeRec(root);
+    return data;
+};
+
+/**
+ * Decodes your encoded data to tree.
+ *
+ * @param {string} data
+ * @return {TreeNode}
+ */
+var deserialize = function (data) {
+    if (!data) {
+        return null;
+    }
+    let curVal = data.shift();
+    if (curVal == 1001) {
+        return null;
+    }
+    let node = new TreeNode(curVal);
+    node.left = deserialize(data);
+    node.right = deserialize(data);
+    return node;
+};
+
+/**
+ * Your functions will be called as such:
+ * deserialize(serialize(root));
+ */