#!/usr/bin/env php
<?php
# shamelessly stolen from https://www.geeksforgeeks.org/prime-factor/
// PHP Efficient program to print all 
// prime factors of a given number to an arr

// function to print all prime  
// factors of a given number n to an arr
function primeFactors($n) {
	$n = abs($n);
	$f = array();
	// Print the number of 
	// 2s that divide n to the arr
	while($n % 2 == 0) 
	{ 
		$f[] = 2;
		$n = $n / 2; 
	} 
	// n must be odd at this  
	// point. So we can skip  
	// one element (Note i = i +2) 
	for ($i = 3; $i <= sqrt($n); $i = $i + 2) { 

		// While i divides n,  
		// print i and divide n 
		while ($n % $i == 0) 
		{ 
			$f[] = $i;
			$n = $n / $i; 
		} 
	} 

	// This condition is to  
	// handle the case when n  
	// is a prime number greater 
	// than 2 
	if ($n > 2) 
		$f[] = $n; 
	
	return $f;
}
$f = array();
for($i = 1; $i <= 100; $i++) { // za vse faktorje v 100!
	fprintf(STDERR, "calculating for %d ... ", $i);
	$x = primeFactors($i);
	fprintf(STDERR, "%s\n", implode(",", $x));
	$f = array_merge($f,$x);
}
var_dump($f);
$r = array_count_values($f);
echo "ŠTEVILK 7 JE V 100! natanko ".$r[7]."\n";
?>