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.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
    public static void main(String[] args) throws Exception {
        // Here your code !
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int cnt = Integer.parseInt(br.readLine());
        int num = 0;
        
        for (int i = 0; i < cnt ; i++){
            int n = Integer.parseInt(br.readLine());
            if(isPrime(n))num = num + 1;
        }
        System.out.println(num);
    }
    
    public static boolean isPrime(int x){
        int j = 0;
        if(x==2)return true;
        if(x%2==0 | x<2)return false;
        j = 3;
        while(j <= Math.sqrt(x)){
            if(x%j==0)return false;
            j = j + 2;
        }
        return true;
    }
};