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)

fn read<T: std::str::FromStr>() -> T {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    n.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().split_whitespace()
        .map(|e| e.parse().ok().unwrap()).collect()
}

fn count_nunber_of_prime_number(v: &Vec<u32>) -> u32 {
    let mut ans = 0;
    for x in v {
        if is_prime(*x) {
            ans += 1;
        }
    }
    ans
}

fn is_prime(x: u32) -> bool {
    let mut ret = true;
    let sqrt_x = (x as f64).sqrt() as u32;
    for n in 2..sqrt_x + 1 {
        if x % n == 0 {
            ret = false;
        }
    }
    ret
}

fn main() {
    let n = read::<u32>();
    let mut v = Vec::<u32>::new();
    for _ in 0..n {
        let x = read::<u32>();
        v.push(x);
    }

    println!("{}", count_nunber_of_prime_number(&v));
}