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;

public class Main {

	public static void main(String[] args) {
		int k,i;
		int count = 0;
		Scanner in = new Scanner(System.in);
		int n = Integer.parseInt(in.nextLine());
		int array[] = new int[n];
		for(i=0;i<n;i++)array[i] = Integer.parseInt(in.next());
		for (k=0;k<n;k++){
			if (isprime(array[k])){
				count++;
		}
	}
		System.out.println(count);
}

	public static boolean isprime(int x) {
		int i = 3;
		if (x == 2)
				return true;
		if (x < 2 || x % 2 == 0 )
				return false;
		while (i <= Math.sqrt(x)){
			if (x % i == 0){
				return false;
			}
			i = i+2;
		}
		return true;
	}
}