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)

n = gets.to_i
primes = []

n.times do
  num = gets.to_i

  next if num == 1

  if num == 2
    primes << num
  elsif num.even?
    next
  else
    last = primes.last

    primes.each do |i|
      break if num % i == 0

      if i == last
        primes << num
      end
    end
  end
end

puts primes.length