Online PHP editor | perf for VfJku

<?php function wordsToArr2($str) { $words = [$str]; while ($pos =strpos ( $str , ' ')) { $str=substr($str,($pos+1)); $words[] =$str; } return $words; } function wordsToArr3($str) { $base = array_reverse(explode(' ', $str)); $words = [$placeholder = array_shift($base)]; foreach ($base as $word) { $words[] = $placeholder = $word . ' ' . $placeholder; } return array_reverse($words); } function wordsToArr4($str) { $base = explode(' ', $str); end($base); $l = key($base); $words = [$placeholder = $base[$l--]]; for ($i=$l; $i>=0;$i--) { $words[] = $placeholder = $base[$i] . ' ' . $placeholder; } return array_reverse($words); } function wordsToArr5($str) { $base = str_word_count($str, 1); $l = count($base)-1; $words = [$placeholder = $base[$l--]]; for ($i=$l; $i>=0;$i--) { $words[] = $placeholder = $base[$i] . ' ' . $placeholder; } return array_reverse($words); } function bench($callback, $arg, $runs = 100) { $t = 0; $now = microtime(true); for ($i=0; $i<$runs; $i++) { $callback($arg); } $t += (microtime(true) - $now); return [number_format($t, 8), $i]; } $sentence = 'The quick brown fox jumps over the lazy dog'; list($t, $i) = bench('wordsToArr2', $sentence); echo 'strpos '. $i .' times in: ' . $t . '/sec' . PHP_EOL; list($t, $i) = bench('wordsToArr3', $sentence); echo 'concat '. $i .' times in: ' . $t . '/sec' . PHP_EOL; list($t, $i) = bench('wordsToArr4', $sentence); echo 'end/key '. $i .' times in: ' . $t . '/sec' . PHP_EOL; list($t, $i) = bench('wordsToArr5', $sentence); echo 'count-- '. $i .' times in: ' . $t . '/sec' . PHP_EOL;

Version	System time (s)	User time (s)	Memory (MiB)
7.3.1	0.016	0.005	16.29
7.3.0	0.018	0.006	16.60
7.2.13	0.016	0.005	16.45
7.2.12	0.013	0.010	16.77
7.2.11	0.010	0.010	16.67
7.2.10	0.016	0.006	16.72
7.2.9	0.016	0.009	16.65
7.2.8	0.012	0.006	16.53
7.2.7	0.011	0.005	16.52
7.2.6	0.007	0.011	16.58
7.2.5	0.009	0.010	16.64
7.2.4	0.007	0.011	16.63
7.2.3	0.006	0.012	16.76
7.2.2	0.011	0.007	16.46
7.2.1	0.010	0.008	16.67
7.2.0	0.005	0.012	16.79
7.1.25	0.010	0.013	15.54
7.1.23	0.008	0.004	15.35
7.1.22	0.007	0.007	15.42
7.1.21	0.009	0.006	15.41
7.1.20	0.010	0.003	15.31
7.1.19	0.009	0.005	15.40
7.1.18	0.012	0.006	15.65
7.1.17	0.007	0.008	15.50
7.1.16	0.013	0.003	15.51
7.1.15	0.010	0.007	15.70
7.1.14	0.012	0.003	15.41
7.1.13	0.010	0.003	15.56
7.1.12	0.003	0.013	15.34
7.1.11	0.003	0.011	15.41
7.1.10	0.003	0.012	15.56
7.1.9	0.006	0.010	15.40
7.1.8	0.008	0.008	15.70
7.1.7	0.010	0.007	15.52
7.1.6	0.017	0.017	33.33
7.1.5	0.027	0.007	33.36
7.1.4	0.020	0.013	33.72
7.1.3	0.026	0.010	33.38
7.1.2	0.019	0.010	33.32
7.1.1	0.013	0.000	15.43
7.1.0	0.005	0.010	15.41
5.6.38	0.006	0.011	14.42