as constraints given in the problem wants linear solution or nlogn solution for the problem
but the lot of people submitted O(n^2) solution and get AC
there should be strong test cases
LOL 
, I think they forgot to add " sum of n over all test cases <=1000" 
BTW It can be solved using lower_bound for the given constraints.
I also written solution using two loops
But i dont think so it was Quadratic in time
Because i optimized the inner loop in such way that i took absolute diff until it decreasing and stopped when absolute diff started increasing
So as per my observation inner loop will not take O(n)
time
So it got accepted .
Lets say we have
-5 -1 3 5 6
-4 -2 0 4 7
first
abs(-5-(-4)) = 1
then
abs(-5-(-2)) = 3
break ;
as 3 > 1 the abs diff started increasing i breaked inner loop
for -1
abs(-1-(-4)) = 3
abs(-1-(-2)) = 1
abs(-1-0) = 1
abs(-1-4) = 5
since 5 >1 break inner loop
Also another optimization is if once you got abs diff as 0 you need not to check for any next elements as 0 is least in abs difference .