Given an array having both positive an negative integers. The task is to complete the function maxLen() which returns the length of maximum subarray with 0 sum. The function takes two arguments an array A and n where n is the size of the array A.

Input:
The first line of input contains an element T denoting the number of test cases. Then T test cases follow. Each test case consist of 2 lines. The first line of each test case contains a number denoting the size of the array A. Then in the next line are space separated values of the array A.

Output:
For each test case output will be the length of the largest subarray which has sum 0.

User Task:
Sinec this is a functional problem you don't have to worry about input, you just have to complete the function maxLen().

Constraints:
1 <= T <= 100
1 <= N <= 100
-1000 <= A[] <= 1000

Example:
Input
1
8
15 -2 2 -8 1 7 10 23

Output
5

Explanation
Testcase 1: In the above test case the largest subarray with sum 0 will be -2 2 -8 1 7.

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