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: Accepted)

n=gets.chomp.to_i
ary=Array.new(n)
k=0
for i in 0..n-1
	ary[i]=gets.chomp.to_i
	root=Math.sqrt(ary[i]).to_i
	j=3
			if ary[i]==2 || ary[i]==3 || ary[i]==5 || ary[i]==7
				k += 1
#				print(k,"?´???°1\n")
			elsif ary[i]<2 || ary[i]%2==0
#				puts "?´???°??§?????????1"
			else
				while j <= root
#					print(j,"j??????\n")
					if ary[i]%j==0
						break # puts "?´???°??§?????????2"
					elsif j+2>root &&  ary[i]%j!=0
						k += 1
						break  #print("j=",j," k=",k," ?´???°2\n")
					end
					j+=2
				end
			end
end
puts k