
ZOJ Problem Set  3860
Whoooa! There is a spy in Marjar University. All we know is that the spy has a special ID card. Please find him out! InputThere are multiple test cases. The first line of input contains an integer T indicating the number of test cases. For each test case: The first line contains a integer N (3 ≤ N ≤ 100), which describes that there are N students need to be checked. The second line contains N integers indicating the ID card number of N students. All ID card numbers are 32bit integers. OutputFor each test case, output the ID card number which is different from others. Sample Input3 10 1 1 1 1 1 1 1 1 6 1 3 9 9 8 5 90016 90016 90016 2009 90016 Sample Output6 8 2009 Author: DAI, Longao Source: The 15th Zhejiang University Programming Contest 