Longest Balanced Sub-Sequence

A sequence is balanced when the number of positive values in it equals the number of negative values.

Given a sequence, find the length of the longest balanced sub-sequence made of consecutive elements.

The first line contains the number of test cases $T$ ($1 \le T \le 15$).

Each test case takes two lines. The first line contains the length of the sequence $N$ ($0 \le N \le 100000$). The second line contains $N$ non-zero 32-bit signed integers separated by spaces. If $N = 0$, the second line is empty.

For each test case, print one line in the format Case #x: M, where $x$ is the test case number starting from 1 and $M$ is the length of the longest balanced sub-sequence of consecutive elements. If no balanced sub-sequence exists, $M$ is 0.

For the first test case, the answer is (-5 1 -7 8) or (1 -7 8 -6). Each holds two positive and two negative values.

For the second test case, the answer is (9 -9 -1 6 -7 -1 2 8 3 1 -2 -1), which holds six positive and six negative values.