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 Ruby (judge verdict: Wrong Answer)

require 'prime'

n = gets.chomp.to_i
i = 0
j = 0
count = 0
arr = []
p = []


n.times{
    a = gets.chomp.to_i
    if a != 2 && a.even?
        next
    else
        arr[i] = a
        i += 1
    end
}

Prime.each(100000){ |prime|
    p[j] = prime
    j += 1
}

arr.each{ |k|
    p.include?(k) && count += 1
}

puts count