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: Time Limit Exceeded)

using System;

class Program
{
    static void Main()
    {
        int n = int.Parse(Console.ReadLine());
        int[] a = new int[n];
        for (int i = 0; i < a.Length; i++)
        {
            a[i] = int.Parse(Console.ReadLine());
        }

        int count = 0;
        for(int i = 0;i < a.Length; i++)
        {
            int dcount = 0;
            if (a[i] % 2 == 0 && a[i] != 2)
                continue;
            else
            {
                for (int j = a[i]; j > 1; j--)
                {
                    if (a[i] % j == 0)
                        dcount++;
                    if (dcount > 1)
                        break;
                }
                if (dcount == 1)
                    count++;
            }
        }
        Console.WriteLine(count);
    }
}