Problem:
Prime Numbers

A prime number is a natural number which has exactly two distinct natural number divisors: 1 and itself. For example, the first four prime numbers are: 2, 3, 5 and 7.

Write a program which reads a list of N integers and prints the number of prime numbers in the list.

Input

The first line contains an integer N, the number of elements in the list.

N numbers are given in the following lines.

Output

Print the number of prime numbers in the given list.

Constraints

1 ≤ N ≤ 10000

2 ≤ an element of the list ≤ 108

Sample Input 1

5
2
3
4
5
6

Sample Output 1

3

Sample Input 2

11
7
8
9
10
11
12
13
14
15
16
17

Sample Output 2

4

Solution in Rust (judge verdict: Accepted)

/*input
16
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
*/
use std::io::BufRead;

fn main() {
    let stdin = std::io::stdin();
    let mut lines = stdin.lock().lines().map(|l| l.unwrap());
    let n = lines.next().unwrap().parse().unwrap();
    let m = lines.take(n).map(|i| i.parse::<u32>().unwrap());
    println!(
        "{}",
        m.filter(|&i| if i == 2 {
            true
        } else if i % 2 == 0 {
            false
        } else {
            for j in 3..(i as f64).sqrt().floor() as u32 + 1 {
                if i % j == 0 {
                    return false;
                }
            }
            true
        })
        .count()
    );
}