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.Scanner;

class Main {
	public static void main(String args[]) {
		Scanner scanner = new Scanner(System.in);
		int  num = scanner.nextInt();//要素数
		int count = 0;
		int prime_num = 0;
		boolean prime = false;
		
		while( count < num ) {
			prime = isPrime(scanner);
			if( prime ) {
				prime_num ++;
			}
			count ++;
		}

		 System.out.println(prime_num);
		
		scanner.close();
	}

	public static boolean isPrime(Scanner scanner) {
		int  num = scanner.nextInt();//要素数
		
	    if (num == 2) return true;
	    else if (num % 2 == 0) return false; // 偶数はあらかじめ除く
	
	    double sqrtNum = Math.sqrt(num);
	    for (int i = 3; i <= sqrtNum; i += 2)
	    {
	        if (num % i == 0)
	        {
	            // 素数ではない
	            return false;
	        }
	    }
	
	    // 素数である
	    return true;
	}
}