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>
#include <stdlib.h>
#include <math.h>

int check(int n){
	int i;
	if(n == 2) return 1;
	if(n < 2 || n % 2 == 0) return 0;
	for(i = 3; i <= sqrt((double)n); i += 2){
		if(n % i == 0) return 0;
	}
	return 1;
}

int main(){
	int n, i;
	int *a;
	int prime = 0;

	scanf("%d", &n);
	a = (int*)malloc(sizeof(int)*n);

	for(i = 0; i < n; i++){
		scanf("%d", a+i);
		prime += check(*(a+i));
	}

	printf("%d\n", prime);

	return 0;
}