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 Python (judge verdict: Time Limit Exceeded)

def isPrimeNum(x):
	# for speed up
	if x == 2 or x == 3 or x == 5 or x == 7 or x == 11:
		return True
	if x % 2 == 0 or x % 3 == 0 or x % 5 == 0 or x % 7 == 0 or x % 11 == 0:
		return False

	# check by only odd number 
	i = 13
	while i < x:
		if x % i == 0:
			return False
		i += 2
	return True

# input
n = int(raw_input())

if n < 1 or n > 10000:
	exit()

count = 0

for i in range(0, n):
	e = int(raw_input())
	if e < 2 or e > 1000000000:
		exit()
	if isPrimeNum(e):
		count += 1

print count