Given an array of size **n**. The task is to find the longest subsequence such that absolute difference between adjacents is one. Time Complexity of O(n) is required.

Examples: Input : arr[] = {10, 9, 4, 5, 4, 8, 6} Output : 3 As longest subsequences with difference 1 are, "10, 9, 8", "4, 5, 4" and "4, 5, 6". Input : arr[] = {1, 2, 3, 2, 3, 7, 2, 1} Output : 7 As longest consecutive sequence is "1, 2, 3, 2, 3, 2, 1".

**Input:**

The first line consists of an integer **T** i.e number of test cases. The first line of each test case consists of an integer **n**.The next line consists of **n** spaced integers.

**Output:**

Print the required answer.

**Constraints: **

1<=T<=100

1<=n,a[i]<=100000

**Example:
Input:**

2

7

10 9 4 5 4 8 6

8

1 2 3 2 3 7 2 1

**Output:**

3

7

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