Singleton Number

Given an array of integers, every element appears twice except for one. Your task is to find that single number using an efficient bitwise algorithm. A particularly useful property is that for any integer \(a\), the operation \(a \oplus a = 0\) and \(a \oplus 0 = a\). By applying the XOR operation sequentially to all numbers in the array, you can isolate the unique element.

inputFormat

The input consists of two lines:

• The first line contains a single integer \(n\), representing the number of elements in the array.
• The second line contains \(n\) space-separated integers.

outputFormat

Output a single integer representing the number that appears only once in the array.

1
1

1