SingleNumber
Given an array of integers, every element appears three times except for one. Find that single one.
Input
There are multiple test cases. Each case contains a positive integer n(0<n<10^5), followed by n positive numbers. All the numbers in the input are less than 2^31.
Output
Print the element appears only once
Sample Input
7
3 5 3 1 3 5 5
Sample Output
1