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)

import scala.io.StdIn

object Main extends App {

  val n = StdIn.readLine().trim.toInt
  
  def isPrime(x: Int): Boolean = {
    if (x == 2) {
      true
    }
    else if (x < 2 || x % 2 == 0) {
      false
    } else {
      !(3 to scala.math.sqrt(x).toInt by 2).exists(i => x % i == 0)
    }
  }

  println((0 until n).foldLeft(0){ (acc, _) =>
    val x = StdIn.readLine().trim.toInt
    acc + (if(isPrime(x)) 1 else 0)
  })

}