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 PHP (judge verdict: Accepted)

<?php
	$n = trim( fgets( STDIN ) );
	$nums = [];
	for( $i=0; $i<$n; $i++ ) {
		array_push( $nums, intval( trim( fgets( STDIN ) ) ) );
	}
	$cnt = $n;
	$nums2 = [];
	$size = count( $nums );
	for( $j=0; $j<$size; $j++ ) {
		if( 0 == $nums[$j]%2 ) {
			if( 2 != $nums[$j]) { $cnt--; }
		} else {
			array_push( $nums2, $nums[$j] );
		}
	}
	$nums = $nums2;
	$end = max( $nums );
	sort( $nums );
	for( $i=3; $i*$i<=$end; $i+=2 ) {
		$nums2 = [];
		$size = count( $nums );
		for( $j=0; $j<$size; $j++ ) {
			if( 0 == $nums[$j]%$i )  {
				if( $nums[$j] != $i ) {
					$cnt--;
				}
			} else {
				array_push( $nums2, $nums[$j] );
			}
		}
		$nums = $nums2;
	}
	print $cnt;
?>