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 <math.h>

int isPrime(int n)
{
    if(n == 2)
    {
        return 1;   
    }

    if(n % 2 == 0 || n < 2)
    {
        return 0;
    }

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

    return 1;
}

int main(void)
{
    int n;
    scanf("%d", &n);
    
    int count = 0;
    int i;
    for(i = 0; i < n; ++i)
    {
        int x;
        scanf("%d", &x);
        count += isPrime(x);
    }

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

    return 0;
}