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)

pub fn read_parameters<T>() -> Result<Vec<T>, String>
where
    T: std::str::FromStr,
{
    let mut line = String::new();

    std::io::stdin()
        .read_line(&mut line)
        .map_err(|err| format!("{:?}", err))?;

    line.trim()
        .split_whitespace()
        .map(|x| x.parse::<T>())
        .collect::<Result<Vec<T>, _>>()
        .map_err(|_| format!("{}", "parse error"))
}

fn is_prime(n: usize) -> bool {
    if n == 1 {
        return false;
    }
    if n == 2 {
        return true;
    }
    if n % 2 == 0 {
        return false;
    }
    let mut d = 3;
    while d * d <= n {
        if n % d == 0 {
            return false;
        }
        d += 2;
    }
    return true;
}
fn main() {
    let n = read_parameters::<usize>().unwrap();

    let mut x = Vec::new();
    for _ in 0..n[0] {
        let a = read_parameters::<usize>().unwrap();
        x.push(a[0]);
    }
    let count = x
        .into_iter()
        .filter(|&n| is_prime(n))
        .collect::<Vec<_>>()
        .len();
    println!("{}", count);
}