Lone Integer

You are given a list of integers nums where each integer occurs exactly three times except for one which occurs once. Return the lone integer.

Bonus: solve it in \(\mathcal{O}(1)\) space.

Constraints

• n ≤ 100,000 where n is length of nums

https://binarysearch.com/problems/Lone-Integer

Examples

Example 1

Input

• nums = [2, 2, 2, 9, 5, 5, 5]

Output

• answer = 9

Example 2

Input

• nums = [7, 1, 1, 1]

Output

• answer = 7

Solution