[Basic] Find the Odd Occurence

Given an array of positive integers. All numbers occur even number of times except one number which occurs odd number of times. Find the number.

Expected Time Complexity: O(n)
Expected Auxiliary Space​: Constant

Input:

The first line of input contains a single integer T denoting the number of test cases. Then T test cases follow. Each test case consist of two lines.

The first line of each test case consists of an integer N, where N is the size of array. The second line of each test case contains N space separated integers denoting array elements.

Output:

Corresponding to each test case, print in a new line, the number which occur odd number of times.

Constraints:

1 ≤ T ≤ 100
1 ≤ N ≤ 202
1 ≤ A[i] ≤ 1000

Example:

Input:
1
5
8 4 4 8 23

Output:
23

t = int(input())

for i in range(t):
    n = int(input())
    numbers = [str(x) for x in input().split()]
    result = []
    for j in range(n):
        if numbers[j] not in result:
            result.append(numbers[j])
        else:
            result.remove(numbers[j])
    print(' '.join(result))

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