Given a Binary Tree, print Left view of it. Left view of a Binary Tree is set of nodes visible when tree is visited from Left side. The task is to complete the function **leftView()**, which accepts root of the tree as argument.

Left view of following tree is 1 2 4 8.

1

/ \

2 3

/ \ / \

4 5 6 7

\

8

**Input:**

The input contains **T**, denoting number of testcases. For each testcase there will be two lines. The first line contains number of edges. The second line contains two nodes and a character separated by space. The first node denotes data value, second node denotes where it will be assigned to the previous node which will depend on character '**L**' or '**R**' i.e. the 2nd node will be assigned as left child to the 1st node if character is 'L' and so on. The first node of second line is **root node**. The struct or class **Node** has a data part which stores the data, pointer to left child and pointer to right child. There are multiple test cases. For each test case, the function will be called individually.

**Output:**

The function should print nodes in left view of Binary Tree.

**User Task:**

Since this is a functional problem you don't have to worry about input, you just have to complete the function **leftView().**

**Constraints:**

1 <= T <= 100

1 <= Number of nodes <= 100

1 <= Data of a node <= 1000

**Example:
Input:**

2

2

1 2 R 1 3 L

4

10 20 L 10 30 R 20 40 L 20 60 R

**Output:**

1 3

10 20 40

**Explanation:
Testcase 2:** below is a given tree with its nodes.

We can clearly see that nodes which are at left view of tree they are 10 20 40.

Author: kartik

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