2557.Savior

Time Limit: 1s Memory Limit: 256MB

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 \neq 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 Format(From the terminal/stdin)

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

Output Format(To the terminal/stdout)

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

Sample Input 1

Copy
1
2
 \n
 \n

Sample Output 1

Copy
1
 \n

Sample Input 2

Copy
2
1 2
 \n
 · \n

Sample Output 2

Copy
2
 \n

Sample Input 3

Copy
2
3 5
 \n
 · \n

Sample Output 3

Copy
1
 \n

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