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 C# (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication3
{
    class Program
    {
        static bool prime(int input)
        {
            if (input < 2)
                return false;
            if (input == 2)
                return true;
            if (input % 2 == 0)
                return false;
            double data2 = Math.Sqrt(input);
            for (int i = 3; i <= data2; i += 2)
            {
                if (input % i == 0)
                    return false;

            }
            return true;
        }

        static void Main(string[] args)
        {
            string temp;
            int number;
            int result = 0;
            temp = Console.ReadLine();
            number = int.Parse(temp);

            for (int i = 0; i < number; i++)
            {
                temp = Console.ReadLine();
                if(prime(int.Parse(temp)) == true)
                    result++;

            }


            Console.WriteLine("{0}", result);
        }
    }
}