Problem Statement :

As you all know, a dance party was organized for the unfortunate souls who had decided to join this cursed institution. Needless to say it was meant for those who were desperate enough to jump into a relationship less than a month into meeting someone of the opposite sex. The tickets were sold in pairs, wherein partners ended up with tickets with the same ID. The party is set to begin only after everyone who bought the ticket has entered the arena. Also, the organizers of the party need to make sure that there are only couples inside and they have resorted to you for help. The problem is that, the partners need not necessarily come in together. Given the total number of people inside, and their Ticket IDs, you need to find out the ID of the ticket the Forever Alone Guy used to make his way into the party.

Input :

There are multiple input sets, and for each the first line referes to 'N' - the total number of people of who came to party, followed by 'N' lines that contain the Ticket IDs of the people who came to party. Assume that everyone who decided to waste their money turned up for the party.

Output :

The output for each test case consists of a single line that prints out the Ticket ID of the Forever Alone Guy.

Constraints :

1 <= N <= 10^6 where N is always odd
1 < Ticket IDs < 10^18

Sample Input :

``` 5 100 666 123 100 123 7 1001 2002 3003 1001 4004 3003 2002 ```

Sample Output :

``` Forever Alone Guy : 666 Forever Alone Guy : 4004 ```

Problem Setter : Vishnu Mohandas

Languages: C,C++,Java

Time Limit: 1 Second(s)
Score: 100 Point(s)
Input File Limit: 50000 Bytes

Mode Judge

RankNameScore
1xyz0
2Ams0
3TIP0
4team420
5xyzz0
6asdasdasd0
7abcd0
8khankhan0
9Gabriel0
10gigel0