添加（199.二叉树的右视图）：增加typescript版本

problems/0102.二叉树的层序遍历.md

@@ -709,7 +709,28 @@ var rightSideView = function(root) {
 };
 ```
 
+TypeScript：
+
+```typescript
+function rightSideView(root: TreeNode | null): number[] {
+    let helperQueue: TreeNode[] = [];
+    let resArr: number[] = [];
+    let tempNode: TreeNode;
+    if (root !== null) helperQueue.push(root);
+    while (helperQueue.length > 0) {
+        for (let i = 0, length = helperQueue.length; i < length; i++) {
+            tempNode = helperQueue.shift()!;
+            if (i === length - 1) resArr.push(tempNode.val);
+            if (tempNode.left !== null) helperQueue.push(tempNode.left);
+            if (tempNode.right !== null) helperQueue.push(tempNode.right);
+        }
+    }
+    return resArr;
+};
+```
+
 Swift:
+
 ```swift
 func rightSideView(_ root: TreeNode?) -> [Int] {
     var res = [Int]()