43 lines
693 B
PHP
43 lines
693 B
PHP
<?php
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error_reporting(E_ALL);
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ini_set('display_errors', '1');
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function get_primes7($n) {
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if ($n < 2) return array();
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if ($n == 2) return array(2);
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$s = range(3, $n, 2);
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$mroot = sqrt($n);
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$half = count($s);
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$i = 0;
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$m = 3;
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while ($m <= $mroot) {
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if ($s[$i]) {
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$j = (int)(($m*$m - 3) / 2);
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$s[$j] = 0;
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while ($j < $half) {
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$s[$j] = 0;
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$j += $m;
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}
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}
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$i = $i + 1;
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$m = 2*$i + 3;
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}
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$res = array(2);
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foreach ($s as $v) {
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if ($v) {
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$res[] = $v;
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}
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}
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return $res;
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}
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$startTime = time();
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$periodTime = getenv('RUN_TIME');
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$res = array();
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for ($i = 0; $i < 30; $i++) {
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$res = get_primes7(10000000);
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print "Found ".count($res)." prime numbers.\n";
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}
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