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 JAVA (judge verdict: Accepted)

import java.util.*;
import java.io.*;
import java.lang.*;

public class Main {
    static final int INF = 1000000000;     
    
    public static void main(String[] args) throws Exception {                
        Scanner input = new Scanner(System.in);
        int n = input.nextInt();
        int res = 0;
        for (int i = 0; i < n; ++i) {
            int x = input.nextInt();
            if (isPrime(x)) ++res;
        }
        System.out.println(res);
    }       
    
    static boolean isPrime(int x) {
        if (x < 2) return false;
        for (int i = 2; i <= Math.sqrt(x); ++i) {
            if (x % i == 0) return false;
        }
        return true;
    }
}