feat: add js solution to lc problem: No.2196

Author: rain84

solution/2100-2199/2196.Create Binary Tree From Descriptions/README.md

@@ -268,6 +268,45 @@ function createBinaryTree(descriptions: number[][]): TreeNode | null {
 }
 ```
 
+#### JavaScript
+
+```js
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {number[][]} descriptions
+ * @return {TreeNode}
+ */
+
+var createBinaryTree = function (descriptions) {
+    const nodes = {};
+    const children = new Set();
+
+    for (const [parent, child] of descriptions) {
+        if (!nodes[parent]) nodes[parent] = new TreeNode(parent);
+        if (!nodes[child]) nodes[child] = new TreeNode(child);
+
+        children.add(child);
+    }
+
+    let root = -1;
+    for (const [parent, child, isLeft] of descriptions) {
+        if (!children.has(parent)) root = parent;
+
+        if (isLeft) nodes[parent].left = nodes[child];
+        else nodes[parent].right = nodes[child];
+    }
+
+    return nodes[root];
+};
+```
+
 #### Rust
 
 ```rust

solution/2100-2199/2196.Create Binary Tree From Descriptions/README_EN.md

@@ -263,6 +263,45 @@ function createBinaryTree(descriptions: number[][]): TreeNode | null {
 }
 ```
 
+#### JavaScript
+
+```js
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {number[][]} descriptions
+ * @return {TreeNode}
+ */
+
+var createBinaryTree = function (descriptions) {
+    const nodes = {};
+    const children = new Set();
+
+    for (const [parent, child] of descriptions) {
+        if (!nodes[parent]) nodes[parent] = new TreeNode(parent);
+        if (!nodes[child]) nodes[child] = new TreeNode(child);
+
+        children.add(child);
+    }
+
+    let root = -1;
+    for (const [parent, child, isLeft] of descriptions) {
+        if (!children.has(parent)) root = parent;
+
+        if (isLeft) nodes[parent].left = nodes[child];
+        else nodes[parent].right = nodes[child];
+    }
+
+    return nodes[root];
+};
+```
+
 #### Rust
 
 ```rust

solution/2100-2199/2196.Create Binary Tree From Descriptions/Solution.js

@@ -0,0 +1,34 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {number[][]} descriptions
+ * @return {TreeNode}
+ */
+
+var createBinaryTree = function (descriptions) {
+    const nodes = {};
+    const children = new Set();
+
+    for (const [parent, child] of descriptions) {
+        if (!nodes[parent]) nodes[parent] = new TreeNode(parent);
+        if (!nodes[child]) nodes[child] = new TreeNode(child);
+
+        children.add(child);
+    }
+
+    let root = -1;
+    for (const [parent, child, isLeft] of descriptions) {
+        if (!children.has(parent)) root = parent;
+
+        if (isLeft) nodes[parent].left = nodes[child];
+        else nodes[parent].right = nodes[child];
+    }
+
+    return nodes[root];
+};