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
import scala.math.sqrt

object Main{
    def main(args: Array[String]){
        val sc = new java.util.Scanner(System.in)
        val n = sc.nextInt // 最初の数字を読み取る
        val list = List.fill(n)(sc.nextInt) // nextIntがn回呼ばれる
        var count = 0;
        for(j <- list)if(isPrime(j)) count = count + 1
            
        
        println(count)
    }
    
    def isPrime(x: Int): Boolean = {
        if(x == 2){
            return true
        }
        
        if(x < 2 || x % 2 == 0){
            return false
        }
        
        var i = 3;
        while(i <= sqrt(x)){
            if(x % i == 0){
                return false
            }
            i += 2
        }
        return true
    }
}