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: Time Limit Exceeded)

n = gets.chomp.to_i
data = Array.new(0)
n.times { |i|
	data[i] = gets.chomp.to_i
}
data.sort!
prime = [2]

for i in 3..data[n-1]
    j = 0
    flg = 1
    while j < prime.length
        if i % prime[j] == 0
            flg = 0
            break
        end
        j+=1
    end
    if flg == 1
        prime[j] = i
    end
end

cnt=0
i = 0
j = 0
while i<data.length && j<prime.length
    if data[i] == prime[j]
        cnt+=1
        i+=1
        j+=1
    elsif data[i] < prime[j]
        i+=1
    else
        j+=1
    end
end
puts cnt