The test cases miss a basic case of '1 2 2 3 3 5'. A lot of answers submitted here give wrong answer for this case (3 instaed of 4).

Should be subsequence how about fixing it hackerrank

It should be a sequence not a subarray to be more clear, as it is counting non-contiguous elements as valid.

Python

def pickingNumbers(a):
    # Write your code here
    record = []
    for element_original in sorted(a):
        l = []
        for element_copy in sorted(a):
            l.append(element_original - element_copy)
        record.append(max(l.count(0) + l.count(1), l.count(0) + l.count(-1)))
    return max(record)

The question should read: "give the length of the longest chain of numbers that meet the criterion that you can make with the numbers in the array".