CF665D Simple Subset

A tuple of positive integers $ {x_{1},x_{2},...,x_{k}} $ is called simple if for all pairs of positive integers $ (i,j) $ ( $ 1

The first line contains integer $ n $ ( $ 1

On the first line print integer $ m $ — the maximum possible size of simple subset of $ a $ . On the second line print $ m $ integers $ b_{l} $ — the elements of the simple subset of the array $ a $ with the maximum size. If there is more than one solution you can print any of them. You can print the elements of the subset in any order.