Find the Odd Occurence

PROBLEM :
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

--------------------------------------------------------------------------------
SIMPLE c++ IMPLEMENTATION :
--------------------------------------------------------------------------------

#include<iostream>
using namespace std;
int main()
{
int t ;
        cin>>t ;
        while(t--)
        {
            int no ;
            cin>>no ;
            int arr[no] ;
            for(int i=0;i<no;i++)
                cin>>arr[i] ;
               
            int Xor=0 ;
            for(int i=0;i<no;i++)
                Xor^=arr[i] ;
               
            cout<<Xor<<endl ;
        }
return 0;
}

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