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 = 'abcdefgh'; $len = strlen($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)
8.3.60.0170.25430.32
8.3.50.0280.28427.47
8.3.40.0270.25029.83
8.3.30.0230.24931.47
8.3.20.0230.14730.03
8.3.10.0130.16333.21
8.3.00.0030.13535.84
8.2.180.0230.25428.14
8.2.170.0170.24029.90
8.2.160.0230.26431.47
8.2.150.0030.13529.89
8.2.140.0070.13631.81
8.2.130.0030.14134.46
8.2.120.0100.12931.89
8.2.110.0130.19831.47
8.2.100.0100.18529.03
8.2.90.0030.18830.32
8.2.80.0170.17528.75
8.2.70.0100.18928.61
8.2.60.0100.18529.15
8.2.50.0070.19228.75
8.2.40.0070.18829.47
8.2.30.0100.17230.73
8.2.20.0100.18428.84
8.2.10.0070.18629.10
8.2.00.0030.18028.99
8.1.280.0270.22332.20
8.1.270.0130.12336.65
8.1.260.0130.12134.77
8.1.250.0200.15236.86
8.1.240.0030.18438.71
8.1.230.0200.16535.43
8.1.220.0130.17732.31
8.1.210.0130.16233.52
8.1.200.0130.18431.83
8.1.190.0070.17931.96
8.1.180.0170.16831.95
8.1.170.0070.17533.11
8.1.160.0070.18233.49
8.1.150.0130.16833.22
8.1.140.0100.17532.16
8.1.130.0100.17332.41
8.1.120.0030.18332.08
8.1.110.0070.17831.95
8.1.100.0000.19031.98
8.1.90.0070.18332.02
8.1.80.0070.17332.00
8.1.70.0030.17832.06
8.1.60.0170.18132.20
8.1.50.0120.18232.07
8.1.40.0000.19632.08
8.1.30.0030.19432.10
8.1.20.0100.18532.18
8.1.10.0130.18732.13
8.1.00.0100.18632.13
8.0.300.0100.17334.43
8.0.290.0130.17431.39
8.0.280.0170.16632.98
8.0.270.0030.17831.73
8.0.260.0130.17331.17
8.0.250.0130.17731.41
8.0.240.0130.17531.37
8.0.230.0070.18031.48
8.0.220.0070.18531.36
8.0.210.0100.21531.43
8.0.200.0100.17631.39
8.0.190.0160.22131.25
8.0.180.0130.18531.41
8.0.170.0100.18731.28
8.0.160.0100.18631.35
8.0.150.0030.19831.43
8.0.140.0170.18231.36
8.0.130.0070.19127.82
8.0.120.0070.20331.31
8.0.110.0030.19431.42
8.0.100.0100.18631.32
8.0.90.0130.18431.29
8.0.80.0230.29131.27
8.0.70.0130.18131.34
8.0.60.0100.18631.36
8.0.50.0030.19131.34
8.0.30.0300.29631.42
8.0.20.0340.30431.64
8.0.10.0070.18831.47
8.0.00.0380.35731.16
7.4.330.0070.19929.72
7.4.320.0100.18530.92
7.4.300.0130.18330.94
7.4.290.0160.19830.84
7.4.280.0070.20231.05
7.4.270.0030.20331.03
7.4.260.0030.20227.88
7.4.250.0130.20830.84
7.4.240.0130.19630.91
7.4.230.0070.20131.10
7.4.220.0330.43730.89
7.4.210.0200.32431.01
7.4.200.0100.19930.80
7.4.190.0230.18931.10
7.4.160.0270.32530.74
7.4.150.0430.30230.91
7.4.140.0270.32531.07
7.4.130.0340.38530.89
7.4.120.0280.33530.90
7.4.110.0200.32730.81
7.4.100.0200.30730.93
7.4.90.0300.51930.89
7.4.80.0300.32030.85
7.4.70.0310.32931.13
7.4.60.0260.30431.09
7.4.50.0070.17730.64
7.4.40.0100.37030.93
7.4.30.0280.39230.87
7.4.10.0070.41229.14
7.4.00.0130.53429.31
7.3.330.0100.20627.87
7.3.320.0130.25027.93
7.3.310.0100.20730.81
7.3.300.0130.20830.61
7.3.290.0220.38630.71
7.3.280.0240.44730.79
7.3.270.0260.31931.09
7.3.260.0350.44130.86
7.3.250.0500.41831.01
7.3.240.0200.38430.84
7.3.230.0200.33730.89
7.3.210.0200.33931.06
7.3.200.0370.54930.81
7.3.190.0330.46230.84
7.3.180.0330.33630.80
7.3.170.0160.39930.99
7.3.160.0260.33630.86
7.3.130.0170.54429.57
7.3.120.0170.46029.35
7.3.110.0070.57129.32
7.3.100.0170.46429.55
7.3.90.0130.50229.50
7.3.80.0200.53529.51
7.3.70.0170.49729.41
7.3.60.0130.49629.31
7.3.50.0130.51829.26
7.3.40.0170.41029.27
7.3.30.0130.53829.18
7.3.20.0030.44632.74
7.3.10.0030.41132.27
7.3.00.0130.54032.81
7.2.330.0230.33931.27
7.2.320.0200.36430.96
7.2.310.0470.32331.25
7.2.300.0270.35130.99
7.2.290.0330.32731.24
7.2.260.0130.57629.44
7.2.250.0200.57829.52
7.2.240.0070.39929.49
7.2.230.0070.39329.38
7.2.220.0030.44529.59
7.2.210.0200.53129.34
7.2.200.0170.39929.70
7.2.190.0100.54329.28
7.2.180.0200.47829.19
7.2.170.0070.40129.38
7.2.160.0030.46929.65
7.2.150.0030.41233.01
7.2.140.0070.50132.87
7.2.130.0030.45832.93
7.2.120.0100.54832.86
7.2.110.0100.38332.89
7.2.100.0100.47132.63
7.2.90.0070.51432.95
7.2.80.0070.46832.70
7.2.70.0100.53532.97
7.2.60.0000.51332.83
7.2.50.0030.56432.72
7.2.40.0030.42532.95
7.2.30.0100.48232.91
7.2.20.0030.51733.01
7.2.10.0070.53932.96
7.2.00.0100.51933.01
7.1.330.0200.56531.96
7.1.320.0130.71331.91
7.1.310.0070.56131.85
7.1.300.0070.59431.64
7.1.290.0070.69531.61
7.1.280.0070.69931.84
7.1.270.0100.72031.61
7.1.260.0100.69131.86
7.1.250.0100.71231.81
7.1.240.0070.72931.74
7.1.230.0030.74131.87
7.1.220.0070.53931.64
7.1.210.0130.73531.92
7.1.200.0030.57431.51
7.1.190.0000.69231.72
7.1.180.0070.58831.72
7.1.170.0060.73631.52
7.1.160.0070.73431.91
7.1.150.0100.57531.95
7.1.140.0130.72831.85
7.1.130.0070.72231.74
7.1.120.0030.62231.72
7.1.110.0030.69031.91
7.1.100.0100.66831.73
7.1.90.0100.71631.59
7.1.80.0100.62831.76
7.1.70.0030.62331.75
7.1.60.0170.51432.01
7.1.50.0100.62931.97
7.1.40.0070.73531.63
7.1.30.0100.73431.63
7.1.20.0130.60231.79
7.1.10.0070.56631.80
7.1.00.0030.48735.00
7.0.330.0170.72231.23
7.0.320.0170.69631.25
7.0.310.0130.70931.39
7.0.300.0100.73731.23
7.0.290.0070.73931.64
7.0.280.0130.61531.64
7.0.270.0030.56931.34
7.0.260.0030.71931.48
7.0.250.0070.72431.51
7.0.240.0130.72031.39
7.0.230.0100.69731.50
7.0.220.0070.69831.54
7.0.210.0100.74531.34
7.0.200.0130.62331.44
7.0.190.0030.70431.63
7.0.180.0100.73531.58
7.0.170.0030.71831.44
7.0.160.0070.59631.31
7.0.150.0170.65431.57
7.0.140.0050.54734.76
7.0.130.0030.74531.56
7.0.120.0130.65131.47
7.0.110.0100.56131.37
7.0.100.0070.74231.60
7.0.90.0100.57631.46
7.0.80.0100.71431.51
7.0.70.0030.59931.47
7.0.60.0030.75731.67
7.0.50.0130.67731.41
7.0.40.0030.74825.56
7.0.30.0070.74225.79
7.0.20.0130.73325.52
7.0.10.0100.72925.35
7.0.00.0130.73325.34
5.6.400.0371.67251.82
5.6.390.0431.44052.14
5.6.380.0201.73851.85
5.6.370.0401.62551.73
5.6.360.0271.83251.89
5.6.350.0271.56951.91
5.6.340.0201.65051.98
5.6.330.0131.51351.95
5.6.320.0331.58151.95
5.6.310.0401.83552.30
5.6.300.0401.80851.81
5.6.290.0201.90151.61
5.6.280.0131.23555.25
5.6.270.0171.83652.09
5.6.260.0271.87351.99
5.6.250.0271.83252.42
5.6.240.0171.76652.18
5.6.230.0301.44352.16
5.6.220.0171.70352.17
5.6.210.0371.88252.09
5.6.200.0431.44451.84
5.6.190.0271.60352.06
5.6.180.0301.88752.08
5.6.170.0171.47452.18
5.6.160.0331.66952.08
5.6.150.0231.62052.19
5.6.140.0131.87752.34
5.6.130.0231.89751.99
5.6.120.0201.89552.33
5.6.110.0131.45152.27
5.6.100.0271.87552.10
5.6.90.0301.89352.04
5.6.80.0331.80952.20
5.6.70.0271.48252.11
5.6.60.0371.87551.75
5.6.50.0271.84351.83
5.6.40.0231.62951.96
5.6.30.0171.86952.17
5.6.20.0131.87452.06
5.6.10.0271.77451.83
5.6.00.0301.88951.96
5.5.380.0471.90052.23
5.5.370.0531.70652.29
5.5.360.0131.92651.94
5.5.350.0231.74952.13
5.5.340.0501.54752.13
5.5.330.0431.90552.01
5.5.320.0331.47752.18
5.5.310.0371.54651.86
5.5.300.0301.95552.07
5.5.290.0201.94051.92
5.5.280.0301.95152.16
5.5.270.0401.59852.23
5.5.260.0301.72051.78
5.5.250.0201.94551.88
5.5.240.0131.68251.94
5.5.230.0271.56051.76
5.5.220.0331.73952.06
5.5.210.0271.66251.84
5.5.200.0231.79751.68
5.5.190.0271.94651.89
5.5.180.0271.93651.87
5.5.170.0231.94052.30
5.5.160.0271.81652.21
5.5.150.0401.81751.84
5.5.140.0271.70651.86
5.5.130.0201.94351.54
5.5.120.0201.93552.01
5.5.110.0371.93652.12
5.5.100.0301.49151.88
5.5.90.0201.77152.07
5.5.80.0231.60052.04
5.5.70.0331.91552.27
5.5.60.0301.82052.02
5.5.50.0271.93451.93
5.5.40.0301.62751.75
5.5.30.0231.89452.05
5.5.20.0271.69951.83
5.5.10.0271.55051.79
5.5.00.0271.86252.08
5.4.450.0331.74349.03
5.4.440.0271.95048.85
5.4.430.0231.59548.78
5.4.420.0201.89448.63
5.4.410.0431.58548.96
5.4.400.0371.93648.84
5.4.390.0281.97548.54
5.4.380.0271.91548.95
5.4.370.0471.47448.52
5.4.360.0301.58148.83
5.4.350.0331.94948.65
5.4.340.0271.48248.65
5.4.330.0231.92748.98
5.4.320.0201.85948.79
5.4.310.0501.80348.82
5.4.300.0201.65248.76
5.4.290.0301.94848.31
5.4.280.0301.26849.39
5.4.270.0251.48649.38
5.4.260.0261.47149.26
5.4.250.0281.40149.49
5.4.240.0201.52549.31
5.4.230.0311.46049.50
5.4.220.0341.47649.34
5.4.210.0311.33849.43
5.4.200.0231.49149.39
5.4.190.0301.32449.27
5.4.180.0331.42549.37
5.4.170.0331.55849.56
5.4.160.0531.47749.33
5.4.150.0361.27649.20
5.4.140.0251.28149.20
5.4.130.0281.47049.29
5.4.120.0301.37449.25
5.4.110.0301.52149.06
5.4.100.0361.54149.18
5.4.90.0311.31549.21
5.4.80.0331.41349.10
5.4.70.0211.46949.18
5.4.60.0181.28249.15
5.4.50.0331.50349.21
5.4.40.0331.51649.17
5.4.30.0331.47049.22
5.4.20.0351.28449.23
5.4.10.0181.52649.22
5.4.00.0391.52848.92
5.3.290.0231.72547.55
5.3.280.0261.48748.47
5.3.270.0231.74648.54
5.3.260.0371.73148.53
5.3.250.0291.70448.51
5.3.240.0351.74848.42
5.3.230.0301.48048.49
5.3.220.0321.62248.46
5.3.210.0321.76048.45
5.3.200.0321.68348.45
5.3.190.0231.58248.51
5.3.180.0311.51748.55
5.3.170.0241.71148.54
5.3.160.0251.73448.56
5.3.150.0321.75648.54
5.3.140.0241.54148.50
5.3.130.0251.50148.42
5.3.120.0301.79048.48
5.3.110.0371.77348.52
5.3.100.0231.63048.19
5.3.90.0261.45248.21
5.3.80.0301.70648.21
5.3.70.0321.69448.13
5.3.60.0221.57148.14
5.3.50.0241.59947.96
5.3.40.0221.51148.00
5.3.30.0281.52248.14
5.3.20.0251.38147.97
5.3.10.0211.48947.72
5.3.00.0231.37547.71
5.2.170.0241.23245.34
5.2.160.0301.25845.34
5.2.150.0271.25445.34
5.2.140.0411.25945.33
5.2.130.0341.28545.29
5.2.120.0331.67747.04
5.2.110.0361.28345.30
5.2.100.0301.30745.30
5.2.90.0201.23545.29
5.2.80.0141.11333.36
5.2.70.0231.16133.36
5.2.60.0221.16933.32
5.2.50.0161.11633.25
5.2.40.0191.18233.22
5.2.30.0141.10933.20
5.2.20.0181.10533.19
5.2.10.0151.06733.11
5.2.00.0141.13632.98
5.1.60.0241.23238.89
5.1.50.0171.15938.89
5.1.40.0181.18538.87
5.1.30.0201.11039.21
5.1.20.0161.14839.24
5.1.10.0301.17638.98
5.1.00.0241.12838.98
5.0.50.0272.41035.80
5.0.40.0332.42334.67

preferences:
94.17 ms | 400 KiB | 5 Q