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 C++ (judge verdict: Accepted)

#include <iostream>

using namespace std;

bool is_prime(int x)
{
	if (x == 2)
		return true;

	if (x % 2 == 0)
		return false;

	for (int i = 3; i*i <= x; i += 2)
		if (x % i == 0)
			return false;

	return true;
}

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);

	int n;
	cin >> n;

	int count = 0, x;
	while (n--)
	{
		cin >> x;
		count += is_prime(x);
	}

	cout << count << endl;

	return 0;
}