Medium

25.6%

Given a Binary Tree and a positive integer k, count all distinct nodes that are distance k from a leaf node. Here k distance from a leaf means k levels higher than a leaf node. For example if k is more than height of Binary Tree, then nothing should be counted. Expected time complexity is O(n) where n is the number nodes in the given Binary Tree.

**Input:**

The first line of input contains an integer T denoting the number of test cases. Then T test cases follow. Each test case contains an integer n denoting the number of edges. The next line contains edges of the binary tree. The last line contains the value of k.

**Output:**

Count the distinct number of nodes that are at distance k from the lead nodes.

**Constraints:**

1<=T<=100

1<=n<=100

1<=data of node<=100

**Example:
Input:**

2

7

1 2 L 2 4 R 2 5 R 1 3 R 3 6 L 6 8 R 3 7 R

2

5

1 3 L 3 5 L 5 7 L 5 8 R 8 9 R

4

**Output:**

2

1