Longest sub-sequence such that difference between adjacents is one
Submissions: 431   Accuracy:

32.47%

  Difficulty: Easy   Marks: 2

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

** For More Input/Output Examples Use 'Expected Output' option **

Author: saksham0751


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