solution.java

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

    // The sansaXor method
    static int sansaXor(int[] arr) {
        //If array length is even simply return zero
        if(arr.length % 2 == 0)
            return 0;
        //If array length is not even xor all the elements at odd positions
        int ans = 0;
        for(int i = 0; i < arr.length; i ++) {
            // As the array is zero indexed so we would check for index to be even
            // which would mean they are at odd places
            if(i % 2 == 0) {
                ans ^= arr[i];                    
            }
        }
        return ans;
    }

    /* Driver Code */
    private static final Scanner scanner = new Scanner(System.in);
    public static void main(String[] args) throws IOException {
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));
        int t = scanner.nextInt();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");
        for (int tItr = 0; tItr < t; tItr++) {
            int n = scanner.nextInt();
            scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");
            int[] arr = new int[n];
            String[] arrItems = scanner.nextLine().split(" ");
            scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");
            for (int i = 0; i < n; i++) {
                int arrItem = Integer.parseInt(arrItems[i]);
                arr[i] = arrItem;
            }
            int result = sansaXor(arr);
            bufferedWriter.write(String.valueOf(result));
            bufferedWriter.newLine();
        }
        bufferedWriter.close();
        scanner.close();
    }
}