小小蓝的异或消除

题目

import java.util.Scanner;
// 1:无需package
// 2: 类名必须Main, 不可修改

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        sc.nextLine();
        int res = 0;
        for(int i=1;i<=n;i++){
          int m = sc.nextInt();
          res^=m;
        }
        System.out.println(res);
        sc.close();
    }
}