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+#!/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";
+?>