py

sansa and xor

t = int(input())
for i in range(t):
    n = int(input())
    a = [int(x) for x in input().split()]
    
    _sum = a[0]
    
    for i in range(1, n):
        _sum = _sum ^ a[i]
    result = _sum
    step = 2
    while step < n:
        for i in range(n):
            if n - i >= step:
                __sum = a[i]
                for j in range(i + 1, i + step):
                    if j < n:
                        __sum = __sum ^ a[j]
                _sum = _sum ^ __sum
        step += 1
    print(_sum ^ result)