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 JavaScript (judge verdict: Accepted)

const input = require('fs').readFileSync('/dev/stdin', 'utf8').split('\n');
let n = input.map(Number);
let count = 0;
function primeNumber (num) {
    if(num === 2) {
        return true;
    }
    if (num < 2 || num % 2 === 0) {
        return false;
    }
    let i = 3;
    while (i <= Math.sqrt(num)) {
            if(num % i === 0) {
                return false;
            }
            i = i + 2;
    }
    return true;
}

for (i=0; i<n.length; i++) {
    if (primeNumber(n[i])) count++;
}
console.log(count);