Savior

4000ms

262144K

Description:

Misha decided to help Pasha and Akim be friends again. He had a cunning plan — to destroy all the laughy mushrooms. He knows that the laughy mushrooms can easily burst when they laugh. Mushrooms grow on the lawns. There are a[t] mushrooms on the t-th lawn.

Misha knows that the lawns where the mushrooms grow have a unique ability. A lawn (say, i) can transfer laugh to other lawn (say, j) if there exists an integer (say, b) such, that some permutation of numbers a[i], a[j] and b is a beautiful triple (i ≠ j). A beautiful triple is such three pairwise coprime numbers x, y, z, which satisfy the following condition: x² + y² = z².

Misha wants to know on which minimal number of lawns he should laugh for all the laughy mushrooms to burst.

Input:

The first line contains one integer n (1 ≤ n ≤ 10⁶) which is the number of lawns. The next line contains n integers a_i which are the number of mushrooms on the i-lawn (1 ≤ a_i ≤ 10⁷). All the numbers are different.

Output:

Print a single number — the minimal number of lawns on which Misha should laugh for all the mushrooms to burst.

Sample Input:

1
2

Sample Output:

Sample Input:

2
1 2

Sample Output:

Sample Input:

2
3 5

Sample Output:

Informação

Provedor Codeforces

Código CF60D