Medium

60.66%

Given a Binary Tree of size **N**, find size of the **Largest Independent Set(LIS)** in it. A subset of all tree nodes is an independent set if there is no edge between any two nodes of the subset. Your task is to complete the function **LISS()**, which finds the size of the Largest Independent Set.

```
For example:
Consider the following binary tree.The LIS is
LIS: [10, 40, 60, 70, 80]
Size: 5.
```

**Input:**

The function takes a single argument as input, the **root** of the binary tree. There will be **T** test cases and for each test case the function will be called separately.

**Output:**

For each test case function should return the size of the Largest Independent Set (LIS).

**Constraints:**

1<=T<=100

1<=N<=500

**Example:**

**Input:**

2

1 2 R 1 3 L

4

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

**Output:**

2

3

**Note:**The **Input/Ouput** format and **Example** given are used for system's internal purpose, and should be used by a user for **Expected Output** only. As it is a function problem, hence a user should not read any input from stdin/console. The task is to complete the function specified, and not to write the full code.