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 <stdio.h>

int judge(int num)
{
	int i;
	
	if (num < 2){
		return (0);
	}
	if (num == 2){
		return (1);
	}
	if (num % 2 == 0){
		return (0);
	}
	for (i = 3; i * i <= num; i += 2){
		if (num % i == 0){
			return (0);
		}
	}
	return (1);
}

int main(void)
{
	int n, num;
	int ct = 0, i;
	
	scanf("%d", &n);
	for (i = 0; i < n; i++){
		scanf("%d", &num);
		if (judge(num)){
			ct++;
		}
	}
	
	printf("%d\n", ct);
	return (0);
}