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) { $result = ''; for($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); } return $result; } $letters = 'abc'; $r = array(); //echo '1 letters from 4: '; for($i = 0; $i < getPermCount($letters, 1); $i++) $r[] = getPerm($letters, 1, $i); //echo '2 letters from 4: '; for($i = 0; $i < getPermCount($letters, 2); $i++) $r[] = getPerm($letters, 2, $i); //echo ' 3 letters from 4: '; for($i = 0; $i < getPermCount($letters, 3); $i++) $r[] = getPerm($letters, 3, $i); print_r($r);

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)
8.3.60.0130.00316.75
8.3.50.0150.00517.31
8.3.40.0110.01118.68
8.3.30.0150.00418.55
8.3.20.0060.00318.73
8.3.10.0000.00918.95
8.3.00.0040.00419.38
8.2.180.0130.00316.50
8.2.170.0090.00622.96
8.2.160.0130.00718.79
8.2.150.0060.00324.18
8.2.140.0090.00024.66
8.2.130.0080.00026.16
8.2.120.0040.00419.77
8.2.110.0100.00021.03
8.2.100.0090.00317.91
8.2.90.0060.00317.84
8.2.80.0030.00618.03
8.2.70.0040.00417.80
8.2.60.0000.00818.04
8.2.50.0080.00018.10
8.2.40.0000.00821.25
8.2.30.0050.00319.22
8.2.20.0030.00717.79
8.2.10.0000.00817.61
8.2.00.0040.00417.72
8.1.280.0160.00625.92
8.1.270.0050.00523.99
8.1.260.0040.00426.35
8.1.250.0030.00528.09
8.1.240.0000.00922.16
8.1.230.0080.00422.63
8.1.220.0040.00417.74
8.1.210.0040.00418.77
8.1.200.0030.00617.47
8.1.190.0000.00917.23
8.1.180.0040.00419.02
8.1.170.0050.00318.65
8.1.160.0050.00319.01
8.1.150.0000.00918.59
8.1.140.0070.00217.38
8.1.130.0030.00317.36
8.1.120.0040.00417.48
8.1.110.0000.00717.43
8.1.100.0040.00417.46
8.1.90.0040.00417.41
8.1.80.0000.00717.43
8.1.70.0070.00017.43
8.1.60.0030.00517.53
8.1.50.0040.00417.48
8.1.40.0090.00017.39
8.1.30.0090.00017.48
8.1.20.0000.01217.60
8.1.10.0040.00417.55
8.1.00.0020.00517.37
8.0.300.0070.00019.77
8.0.290.0080.00016.75
8.0.280.0000.00818.36
8.0.270.0050.00317.30
8.0.260.0030.00316.81
8.0.250.0030.00516.83
8.0.240.0050.00316.86
8.0.230.0040.00416.96
8.0.220.0000.00716.88
8.0.210.0000.00716.88
8.0.200.0030.00316.93
8.0.190.0000.00716.93
8.0.180.0080.00016.95
8.0.170.0040.00416.79
8.0.160.0030.00316.88
8.0.150.0040.00416.83
8.0.140.0000.01016.73
8.0.130.0000.00613.29
8.0.120.0000.01016.81
8.0.110.0050.00516.94
8.0.100.0050.00216.94
8.0.90.0000.00716.69
8.0.80.0120.00916.82
8.0.70.0040.00416.84
8.0.60.0030.00616.81
8.0.50.0030.00617.00
8.0.30.0110.00617.04
8.0.20.0070.01117.18
8.0.10.0050.00216.83
8.0.00.0080.00916.75
7.4.330.0030.00312.99
7.4.320.0030.00316.43
7.4.300.0030.00316.61
7.4.290.0070.00016.58
7.4.280.0050.00316.59
7.4.270.0040.00416.58
7.4.260.0030.00313.21
7.4.250.0040.00416.52
7.4.240.0030.00316.59
7.4.230.0070.00016.39
7.4.220.0210.00716.64
7.4.210.0060.01416.39
7.4.200.0030.00316.57
7.4.190.0030.00516.47
7.4.160.0090.00616.36
7.4.150.0120.00416.43
7.4.140.0180.00017.86
7.4.130.0130.00716.53
7.4.120.0110.00616.67
7.4.110.0070.01016.29
7.4.100.0070.01016.51
7.4.90.0140.00416.38
7.4.80.0020.01719.39
7.4.70.0080.01216.55
7.4.60.0070.01016.56
7.4.50.0030.00616.13
7.4.40.0070.00716.32
7.4.30.0090.00916.49
7.4.00.0050.00514.80
7.3.330.0030.00313.18
7.3.320.0000.00713.35
7.3.310.0040.00416.34
7.3.300.0060.00016.36
7.3.290.0080.00716.38
7.3.280.0070.01416.33
7.3.270.0040.01516.38
7.3.260.0070.01416.56
7.3.240.0090.00616.57
7.3.230.0170.00716.40
7.3.210.0070.01016.63
7.3.200.0110.00616.59
7.3.190.0110.00416.53
7.3.180.0170.00316.38
7.3.170.0110.01016.55
7.3.160.0120.00316.38
7.3.120.0030.01515.03
7.3.10.0030.01416.41
7.3.00.0000.00816.83
7.2.330.0090.00916.73
7.2.320.0090.01316.68
7.2.310.0110.01216.49
7.2.300.0120.00616.67
7.2.290.0140.00516.49
7.2.130.0040.00817.01
7.2.120.0070.00717.02
7.2.110.0090.00316.98
7.2.100.0030.01017.01
7.2.90.0030.01317.01
7.2.80.0030.01017.13
7.2.70.0040.00716.86
7.2.60.0040.01016.92
7.2.50.0110.00016.78
7.2.40.0060.00616.90
7.2.30.0070.00716.77
7.2.20.0100.00317.01
7.2.10.0070.00716.70
7.2.00.0040.00918.14
7.1.250.0060.00315.70
7.1.200.0080.00815.80
7.1.100.0030.00918.43
7.1.70.0000.00717.21
7.1.60.0140.01019.21
7.1.50.0070.01417.06
7.1.00.0070.07322.43
7.0.200.0000.00916.59
7.0.140.0070.07322.17
7.0.120.0000.07722.09
7.0.60.0070.08020.04
7.0.50.0000.07017.84
7.0.40.0070.04317.75
7.0.30.0130.05017.76
7.0.20.0000.04717.74
7.0.10.0130.06717.81
7.0.00.0070.07017.78
5.6.280.0030.07320.89
5.6.210.0170.07720.48
5.6.200.0100.08018.29
5.6.190.0100.03718.19
5.6.180.0000.05018.23
5.6.170.0100.05318.22
5.6.160.0000.08018.34
5.6.150.0030.05018.29
5.6.140.0100.06718.15
5.6.130.0070.05018.14
5.6.120.0170.07318.15
5.6.110.0030.08318.18
5.6.100.0200.07318.16
5.6.90.0030.08318.17
5.6.80.0130.07017.53
5.6.70.0030.06717.68
5.6.60.0100.07017.49
5.6.50.0100.06317.54
5.6.40.0170.06017.57
5.6.30.0030.05317.59
5.6.20.0070.08017.53
5.6.10.0030.08017.53
5.6.00.0030.07317.52
5.5.350.0200.08020.41
5.5.340.0100.08017.97
5.5.330.0030.06017.95
5.5.320.0100.07318.01
5.5.310.0030.04017.98
5.5.300.0100.06017.97
5.5.290.0100.04317.94
5.5.280.0100.06717.98
5.5.270.0030.08718.04
5.5.260.0000.06317.98
5.5.250.0100.07017.85
5.5.240.0030.05317.38
5.5.230.0170.07017.36
5.5.220.0000.08017.46
5.5.210.0100.07017.32
5.5.200.0000.06717.34
5.5.190.0070.04317.37
5.5.180.0070.08317.33
5.5.160.0030.06317.44
5.5.150.0070.08017.36
5.5.140.0100.07317.32
5.5.130.0100.07717.34
5.5.120.0070.04317.42
5.5.110.0130.07317.32
5.5.100.0000.05317.23
5.5.90.0030.07717.33
5.5.80.0100.08017.22
5.5.70.0100.07717.26
5.5.60.0070.07717.23
5.5.50.0030.07317.32
5.5.40.0070.03717.27
5.5.30.0100.07017.22
5.5.20.0070.08017.32
5.5.10.0000.05317.21
5.5.00.0030.07717.25
5.4.450.0130.05019.29
5.4.440.0070.08319.42
5.4.430.0130.06719.38
5.4.420.0100.04719.44
5.4.410.0070.07719.22
5.4.400.0070.04719.04
5.4.390.0100.07319.12
5.4.380.0170.06319.14
5.4.370.0070.07719.13
5.4.360.0100.07318.89
5.4.350.0100.06719.14
5.4.340.0070.06319.10
5.4.320.0030.06719.13
5.4.310.0000.05318.95
5.4.300.0100.07719.12
5.4.290.0100.08019.05
5.4.280.0070.05018.95
5.4.270.0170.06318.88
5.4.260.0030.06719.13
5.4.250.0100.04719.07
5.4.240.0070.05019.01
5.4.230.0100.06318.95
5.4.220.0070.07718.98
5.4.210.0030.07718.95
5.4.200.0100.06019.00
5.4.190.0100.07019.13
5.4.180.0030.05019.02
5.4.170.0070.04019.11
5.4.160.0100.07718.88
5.4.150.0030.07018.98
5.4.140.0070.06716.60
5.4.130.0070.04016.38
5.4.120.0070.07316.35
5.4.110.0070.07016.47
5.4.100.0130.07016.47
5.4.90.0030.07316.55
5.4.80.0070.04016.51
5.4.70.0030.03716.48
5.4.60.0070.03316.36
5.4.50.0000.03716.45
5.4.40.0030.03316.52
5.4.30.0030.03316.53
5.4.20.0070.03016.36
5.4.10.0070.04016.53
5.4.00.0000.03715.73
5.3.290.0030.06714.73
5.3.280.0070.07314.55
5.3.270.0100.07014.63
5.3.260.0130.07014.59
5.3.250.0030.08314.64
5.3.240.0070.05714.64
5.3.230.0100.06014.46
5.3.220.0000.08014.63
5.3.210.0070.07314.53
5.3.200.0030.08014.58
5.3.190.0070.07714.62
5.3.180.0100.05714.56
5.3.170.0070.04314.62
5.3.160.0000.04714.56
5.3.150.0000.04014.79
5.3.140.0030.03714.41
5.3.130.0070.04014.60
5.3.120.0000.04014.59
5.3.110.0000.04014.62
5.3.100.0030.03314.09
5.3.90.0070.04013.87
5.3.80.0000.04314.02
5.3.70.0070.05314.05
5.3.60.0030.03313.86
5.3.50.0030.03313.96
5.3.40.0000.04313.99
5.3.30.0000.03713.93
5.3.20.0030.03313.75
5.3.10.0030.03313.69
5.3.00.0000.06013.64
5.2.170.0000.03011.16
5.2.160.0030.04311.21
5.2.150.0000.03311.20
5.2.140.0030.03011.18
5.2.130.0000.03011.01
5.2.120.0000.03310.96
5.2.110.0030.03011.00
5.2.100.0000.03011.16
5.2.90.0030.02711.07
5.2.80.0030.02711.30
5.2.70.0030.02711.14
5.2.60.0000.03010.95
5.2.50.0000.03011.05
5.2.40.0030.03011.07
5.2.30.0000.03010.96
5.2.20.0000.03010.95
5.2.10.0000.03010.90
5.2.00.0000.03010.77
5.1.60.0000.0239.84
5.1.50.0000.02710.07
5.1.40.0070.02010.05
5.1.30.0000.02710.38
5.1.20.0030.02710.31
5.1.10.0000.02710.17
5.1.00.0130.02010.14
5.0.50.0000.0208.57
5.0.40.0000.0478.49
5.0.30.0000.0678.29
5.0.20.0030.0378.19
5.0.10.0000.0508.25
5.0.00.0000.0378.16
4.4.90.0000.0177.82
4.4.80.0000.0207.82
4.4.70.0100.0107.82
4.4.60.0030.0137.82
4.4.50.0030.0237.82
4.4.40.0000.0277.82
4.4.30.0000.0177.82
4.4.20.0070.0107.82
4.4.10.0000.0177.82
4.4.00.0030.0307.82
4.3.110.0030.0337.82
4.3.100.0000.0377.82
4.3.90.0000.0337.82
4.3.80.0070.0407.82
4.3.70.0100.0137.82
4.3.60.0070.0307.82
4.3.50.0100.0307.82
4.3.40.0030.0277.82
4.3.30.0000.0377.82
4.3.20.0030.0337.82
4.3.10.0030.0337.82
4.3.00.0000.0307.82

preferences:
64.16 ms | 401 KiB | 5 Q