CF914A Perfect Squares

Given an array $ a_{1},a_{2},...,a_{n} $ of $ n $ integers, find the largest number in the array that is not a perfect square. A number $ x $ is said to be a perfect square if there exists an integer $ y $ such that $ x=y^{2} $ .

The first line contains a single integer $ n $ ( $ 1

Print the largest number in the array which is not a perfect square. It is guaranteed that an answer always exists.

In the first sample case, $ 4 $ is a perfect square, so the largest number in the array that is not a perfect square is $ 2 $ .