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;

namespace AizuOnLine_Lesson
{
    class Program
    {
        static void Main(string[] args)
        {
            List<int> data = Program.GetData();

            int result = 0;
            foreach (int num in data)
            {
                double sqrtNum = Math.Sqrt((double)num);

                bool flag = true;
                for (int i = 2; i <= sqrtNum; i++)
                {
                    if (num % i == 0)
                    {
                        flag = false;
                        break;
                    }
                }

                result += flag ? 1 : 0;
            }

            Console.WriteLine(result);
        }

        private static List<int> GetData()
        {


            List<int> data = new List<int>();

            int count = Convert.ToInt32(Console.ReadLine());

            for (int i = 0; i < count; i++)
            {
                data.Add(Convert.ToInt32(Console.ReadLine()));
            }

            return data;
        }
    }
}