Minimum Communication Groups

You are given several test cases. In each test case, there are n soldiers with given ranks. Two soldiers can communicate directly if their ranks differ by exactly 1. In other words, if two consecutive soldiers in the sorted order have ranks r_i and r_i+1, they belong to the same group if and only if $r_{i+1} - r_{i} = 1$. Otherwise, a new group is required.

Your task is to compute the minimum number of groups required so that every soldier can indirectly communicate with every other soldier in his group via a chain of direct communications.

Input: The first line contains an integer T indicating the number of test cases. For each test case the first number is an integer n (the number of soldiers) followed by n integers representing their ranks.

Output: For each test case, output one integer representing the minimum number of communication groups required. Each answer should be printed on a new line.

inputFormat

The input begins with an integer T (number of test cases). For each test case, the first integer n specifies the number of soldiers, followed by n space-separated integers which denote the ranks of the soldiers.

Example:

2
5 4 1 2 3 5
3 3 10 2

outputFormat

Output the minimum number of groups required for each test case on separate lines.

Example:

1
2

## sample

2
5 4 1 2 3 5
3 3 10 2

1
2

</p>