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;

namespace ALDS1_1_A
{
    class Program
    {
        static void Main(string[] args)
        {
            var line = System.Console.ReadLine();
            var N = System.Int32.Parse(line);
            var num = 0;
            var counter = 0;
            for (var i = 0; i < N; i++) {
                num = System.Int32.Parse(System.Console.ReadLine());

                if (num <= 3)
                {
                    counter++;
                    continue;
                }
                if (num % 2 == 0) continue;
                else
                {
                    if (CheckNum(num))
                    {
                        counter++;
                    }
                }
            }
            System.Console.WriteLine(counter);
        }

        static bool CheckNum(int num) {
            for (var i = 3; i < num - 1; i++) {
                if (num % i == 0) return false;
            }
            return true;
        }
}}