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 Scala (judge verdict: Accepted)

object Main {
  def main(args:Array[String]) = {
    val sc = new java.util.Scanner(System.in)
    val n = sc.nextInt
    val ls = List.fill(n)(sc.nextInt)
    println(ls.filter(i => is_prime(i)).size)
  }
  def is_prime2(n: Int): Boolean = {
    if (n == 2) return true
    //val count = (2 to n).filter(i => i * i <= n).filter(j => n % j == 0).size //memory limit exceeded
    val count_seq = for (i <- 2 to n if i * i <= n; if n % i == 0) yield i //memory limit exceeded
    val count = count_seq.size
    if (count == 0) true else false 
  }
  def is_prime(n: Int): Boolean = {
    if (n == 2)
      return true
    var i = 2
    while (i * i <= n){
      if (n%i == 0){
        return false
      }
      i += 1
    }
    return true
  }
}