Given a Binary Tree and two nodes value **n1** and **n2**. The task is to find the** lowest common ancestor** of the given two nodes.

**Input Format:**

The input contains **T**, denoting number of testcases. For each testcase there will be **third** lines. The first line contains number of edges. The second line contains relation between nodes. 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 third line contains two nodes separated by space for which you have to compute LCA. 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 Format:**

For each testcase, in a new line, print the Lowest Common Ancestor of the two nodes.

**Your Task:**

This is a function problem. You don't have to read the input. Just complete the function **lca() **that takes node, **n1, and n2** as parameter and returns **LCA **node as output.

**Constraints:**

1 <= T <= 100

1 <= Number of nodes <= 100

1 <= Data of a node <= 1000

**Example:**

**Input**

2

2

1 2 L 1 3 R

2 3

3

5 2 L 2 3 L 2 4 R

3 4

**Output **

1

2

**Explanation:
Testcase1: **The tree is

1

/ \

2 3

The LCA of 2 and 3 is 1.

Author: Shubham Joshi 1

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