3v4l.org

run code in 300+ PHP versions simultaneously
<?php // Returns the total number of $count-length strings generatable from $letters. function getPermCount($letters, $count) { $result = 1; // k characters from a set of n has n!/(n-k)! possible combinations for($i = strlen($letters) - $count + 1; $i <= strlen($letters); $i++) { $result *= $i; } return $result; } // Decodes $index to a $count-length string from $letters, no repeat chars. function getPerm($letters, $count, $index) { $result = array(); for($i = 0; $i < $count; $i++) { $pos = $index % strlen($letters); $result[] = $letters[$pos]; $index = ($index-$pos)/strlen($letters); $letters = substr($letters, 0, $pos) . substr($letters, $pos+1); } sort($result); return implode("", $result); } $r = array(); //$letters = 'abcdefghijklm'; $letters = 'abcdefghij'; $len = strlen($letters); for ($c = 1; $c <= $len; $c++) for($i = 0; $i < getPermCount($letters, $c); $i++) $r[] = getPerm($letters, $c, $i); print_r(array_unique($r, SORT_REGULAR));

Here you find the average performance (time & memory) of each version. A grayed out version indicates it didn't complete successfully (based on exit-code).

VersionSystem time (s)User time (s)Memory (MiB)
8.3.60.0271.96868.49
8.3.50.0821.92662.22
8.3.40.0300.97443.00
8.3.30.0600.90244.24
8.3.20.0300.51943.09
8.3.10.0170.49843.77
8.3.00.0130.49647.62
8.2.180.0731.93666.24
8.2.170.0330.92242.88
8.2.160.0530.87944.53
8.2.150.0300.52043.00
8.2.140.0230.48144.35
8.2.130.0170.50244.74
8.2.120.0030.49444.05
8.2.110.0170.77344.48
8.2.100.0200.72141.98
8.2.90.0200.70543.25
8.2.80.0200.70041.56
8.2.70.0070.75541.55
8.2.60.0130.75142.02
8.2.50.0100.76141.65
8.2.40.0230.71442.18
8.2.30.0230.68443.81
8.2.20.0170.73441.55
8.2.10.0100.73941.68
8.2.00.0200.70741.61
8.1.280.0800.87149.57
8.1.270.0170.24938.18
8.1.260.0200.24136.33
8.1.250.0070.25538.35
8.1.240.0100.33638.60
8.1.230.0300.30236.91
8.1.220.0130.33533.85
8.1.210.0030.31335.09
8.1.200.0200.32533.14
8.1.190.0100.33533.60
8.1.180.0130.32933.49
8.1.170.0130.32434.76
8.1.160.0200.32334.83
8.1.150.0170.32534.63
8.1.140.0000.34633.52
8.1.130.0100.32233.89
8.1.120.0130.33133.57
8.1.110.0070.33533.40
8.1.100.0070.34833.50
8.1.90.0170.33833.55
8.1.80.0100.32233.62
8.1.70.0200.31633.50
8.1.60.0100.35833.66
8.1.50.0130.35033.58
8.1.40.0100.35833.57
8.1.30.0070.36033.69
8.1.20.0170.34733.59
8.1.10.0300.74049.56
8.1.00.0200.76449.43
8.0.300.0200.70852.02
8.0.290.0300.69949.04
8.0.280.0130.70050.30
8.0.270.0170.68849.16
8.0.260.0230.71248.68
8.0.250.0130.70748.83
8.0.240.0230.71848.78
8.0.230.0130.73048.86
8.0.220.0070.75248.86
8.0.210.0230.76748.89
8.0.200.0170.72148.70
8.0.190.0200.76248.72
8.0.180.0200.75548.84
8.0.170.0170.75948.73
8.0.160.0200.76348.75
8.0.150.0300.74648.77
8.0.140.0100.77048.83
8.0.130.0401.63679.38
8.0.120.0300.81148.84
8.0.110.0170.76248.77
8.0.100.0100.76148.64
8.0.90.0130.79248.63
8.0.80.0401.20448.73
8.0.70.0270.74348.64
8.0.60.0170.76948.64
8.0.50.0100.76948.83
8.0.30.0831.34948.91
8.0.20.0701.18248.99
8.0.10.0330.73148.75
8.0.00.0741.53248.54
7.4.330.0440.75348.71
7.4.320.0200.73148.40
7.4.300.0170.75848.50
7.4.290.0230.79448.53
7.4.280.0100.82948.29
7.4.270.0130.79148.47
7.4.260.0371.69979.07
7.4.250.0170.82248.27
7.4.240.0230.78948.51
7.4.230.0230.79148.23
7.4.220.0491.13148.50
7.4.210.0501.29448.43
7.4.200.0130.79748.39
7.4.190.0300.78148.42
7.4.160.0371.24348.55
7.4.150.0501.25648.23
7.4.140.0721.27348.45
7.4.130.0771.28648.46
7.4.120.0481.20348.39
7.4.110.0991.60948.53
7.4.100.0431.19548.32
7.4.90.0712.05448.52
7.4.80.0791.43548.39
7.4.70.1131.73848.40
7.4.60.0731.42748.48
7.4.50.0100.64948.34
7.4.40.0231.56448.38
7.4.30.0821.47048.38
7.3.330.0401.77979.38
7.3.320.0231.80079.43
7.3.310.0170.85848.29
7.3.300.0130.85148.24
7.3.290.0691.74848.32
7.3.280.0721.56948.26
7.3.270.0601.38548.70
7.3.260.0781.58048.38
7.3.250.0811.38948.21
7.3.240.0491.40248.51
7.3.230.0661.31948.43
7.3.210.0731.49648.21
7.3.200.0851.68248.18
7.3.190.0821.45848.55
7.3.180.0801.21848.34
7.3.170.0661.37148.54
7.3.160.0561.35248.41
7.2.330.0601.29048.56
7.2.320.0461.46148.72
7.2.310.0891.54148.78
7.2.300.0721.28748.50
7.2.290.0591.31848.67
7.2.90.9800.77729.66
7.2.80.8790.75538.38
7.1.211.0600.76428.90
7.1.200.7060.58125.73
7.0.310.9141.43440.54

preferences:
34.65 ms | 401 KiB | 5 Q