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; } $letters = 'abcd'; echo '2 letters from 4:<br>'; for($i = 0; $i < getPermCount($letters, 2); $i++) echo getPerm($letters, 2, $i).'<br>'; echo '<br>3 letters from 4:<br>'; for($i = 0; $i < getPermCount($letters, 3); $i++) echo getPerm($letters, 3, $i).'<br>';

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)
8.3.60.0070.01018.31
8.3.50.0110.01022.05
8.3.40.0110.00419.02
8.3.30.0110.00420.35
8.3.20.0060.01318.96
8.3.10.0000.00821.17
8.3.00.0060.00319.79
8.2.180.0040.01816.50
8.2.170.0120.00322.96
8.2.160.0040.01120.43
8.2.150.0050.00224.18
8.2.140.0000.00824.66
8.2.130.0070.00026.16
8.2.120.0000.00819.68
8.2.110.0060.00321.06
8.2.100.0060.00617.65
8.2.90.0030.00620.99
8.2.80.0030.00618.05
8.2.70.0050.00317.75
8.2.60.0030.00517.93
8.2.50.0000.00818.07
8.2.40.0040.00419.95
8.2.30.0040.00419.41
8.2.20.0040.00417.68
8.2.10.0080.00017.63
8.2.00.0090.00017.75
8.1.280.0150.00025.92
8.1.270.0070.00023.99
8.1.260.0150.00326.35
8.1.250.0080.00028.09
8.1.240.0060.00322.59
8.1.230.0090.00321.04
8.1.220.0040.00417.78
8.1.210.0040.00718.87
8.1.200.0060.00317.25
8.1.190.0040.00417.23
8.1.180.0040.00418.10
8.1.170.0000.00818.54
8.1.160.0040.00418.96
8.1.150.0000.00818.62
8.1.140.0030.00617.32
8.1.130.0000.00717.70
8.1.120.0060.00317.45
8.1.110.0000.00717.43
8.1.100.0050.00317.37
8.1.90.0000.00717.53
8.1.80.0000.00717.46
8.1.70.0000.00717.48
8.1.60.0030.00617.59
8.1.50.0000.00817.46
8.1.40.0050.00317.50
8.1.30.0080.00017.55
8.1.20.0040.00417.57
8.1.10.0000.00817.57
8.1.00.0120.00017.57
8.0.300.0030.00619.98
8.0.290.0060.00316.75
8.0.280.0070.00018.46
8.0.270.0080.00017.28
8.0.260.0000.00716.75
8.0.250.0000.00717.00
8.0.240.0030.00516.95
8.0.230.0000.00816.87
8.0.220.0030.00317.00
8.0.210.0090.00016.80
8.0.200.0000.00716.99
8.0.190.0000.00816.97
8.0.180.0040.00416.95
8.0.170.0050.00316.78
8.0.160.0040.00416.81
8.0.150.0070.00016.75
8.0.140.0050.00216.93
8.0.130.0060.00313.41
8.0.120.0030.00616.84
8.0.110.0030.00616.92
8.0.100.0050.00216.89
8.0.90.0050.00316.82
8.0.80.0120.00616.88
8.0.70.0020.00516.82
8.0.60.0000.00716.87
8.0.50.0000.00716.97
8.0.30.0090.01117.04
8.0.20.0130.00817.40
8.0.10.0040.00416.86
8.0.00.0110.00916.74
7.4.330.0000.00516.80
7.4.320.0040.00416.54
7.4.300.0050.00316.53
7.4.290.0000.00716.63
7.4.280.0050.00316.61
7.4.270.0030.00316.57
7.4.260.0030.00313.25
7.4.250.0000.00716.58
7.4.240.0030.00316.54
7.4.230.0080.00016.61
7.4.220.0100.01616.48
7.4.210.0060.00916.62
7.4.200.0000.00716.45
7.4.190.0040.00416.68
7.4.160.0060.01216.50
7.4.150.0120.00617.40
7.4.140.0090.01417.86
7.4.130.0110.00616.51
7.4.120.0130.00416.57
7.4.110.0100.01016.49
7.4.100.0090.00816.62
7.4.90.0060.01116.29
7.4.80.0060.01619.39
7.4.70.0000.01716.61
7.4.60.0070.01016.42
7.4.50.0030.00616.60
7.4.40.0070.00322.77
7.4.30.0100.01016.31
7.4.00.0080.00714.79
7.3.330.0000.00513.45
7.3.320.0020.00213.39
7.3.310.0030.00316.39
7.3.300.0000.00616.36
7.3.290.0070.01316.38
7.3.280.0070.00816.33
7.3.270.0090.00917.40
7.3.260.0130.00818.24
7.3.250.0110.01016.51
7.3.240.0130.00316.57
7.3.230.0060.01116.60
7.3.210.0060.01016.50
7.3.200.0110.00619.39
7.3.190.0100.00716.23
7.3.180.0090.00616.31
7.3.170.0170.00016.59
7.3.160.0100.00616.47
7.3.120.0070.00914.88
7.3.110.0090.01114.93
7.3.100.0100.00514.82
7.3.90.0090.00614.92
7.3.80.0070.00714.89
7.3.70.0110.00514.79
7.3.60.0080.00914.91
7.3.50.0080.00414.79
7.3.40.0030.00914.84
7.3.30.0050.00714.74
7.3.20.0100.00516.74
7.3.10.0050.01016.72
7.3.00.0060.00816.78
7.2.330.0170.00016.45
7.2.320.0100.00716.83
7.2.310.0080.01016.77
7.2.300.0090.00916.58
7.2.290.0060.01216.73
7.2.250.0150.00614.79
7.2.240.0050.01414.89
7.2.230.0080.00814.98
7.2.220.0100.00515.31
7.2.210.0100.00515.14
7.2.200.0060.00715.08
7.2.190.0090.00614.92
7.2.180.0070.00814.92
7.2.170.0020.01414.89
7.2.160.0000.01314.75
7.2.150.0000.01716.73
7.2.140.0070.01016.89
7.2.130.0090.00617.13
7.2.120.0030.01316.95
7.2.110.0060.00317.06
7.2.100.0030.01017.10
7.2.90.0110.00716.57
7.2.80.0060.00317.04
7.2.70.0040.01217.18
7.2.60.0030.01316.88
7.2.50.0140.00016.98
7.2.40.0080.00316.57
7.2.30.0060.00616.96
7.2.20.0070.00417.05
7.2.10.0030.01016.98
7.2.00.0040.01218.29
7.1.330.0110.00515.94
7.1.320.0080.00415.78
7.1.310.0020.01315.88
7.1.300.0040.00715.74
7.1.290.0040.01115.73
7.1.280.0030.01015.86
7.1.270.0020.01315.63
7.1.260.0090.00515.74
7.1.250.0000.01015.61
7.1.200.0000.01215.96
7.1.100.0000.01318.09
7.1.70.0040.00417.21
7.1.60.0040.01117.05
7.1.50.0080.00416.78
7.1.40.0040.00816.68
7.1.30.0040.01216.73
7.1.20.0070.01016.97
7.1.10.0030.00616.78
7.1.00.0030.00516.69
7.0.200.0000.00716.93
7.0.190.0030.00616.56
7.0.180.0000.00916.11
7.0.170.0000.01316.36
7.0.160.0030.01316.39
7.0.150.0000.01116.24
7.0.140.0000.00716.63
7.0.130.0080.00016.47
7.0.120.0000.01416.65
7.0.110.0000.01016.40
7.0.100.0030.00616.31
7.0.90.0040.00416.30
7.0.80.0030.01316.55
7.0.70.0000.01216.48
7.0.60.0040.00416.25
7.0.50.0000.00716.51
7.0.40.0000.00915.31
7.0.30.0030.00515.31
7.0.20.0060.00815.31
7.0.10.0070.01015.31
7.0.00.0100.00315.31
5.6.300.0130.04620.58
5.6.290.0100.05020.68
5.6.280.0000.04620.99
5.6.270.0120.03120.99
5.6.260.0030.08221.07
5.6.250.0060.04220.91
5.6.240.0030.05120.88
5.6.230.0030.06520.84
5.6.220.0070.04420.92
5.6.210.0030.07820.64
5.6.200.0030.08720.85
5.6.190.0100.04120.94
5.6.180.0070.04321.04
5.6.170.0030.05420.97
5.6.160.0030.06321.04
5.6.150.0170.03021.00
5.6.140.0060.07820.77
5.6.130.0100.03620.78
5.6.120.0030.04421.03
5.6.110.0100.06920.86
5.6.100.0070.04320.76
5.6.90.0130.06920.73
5.6.80.0030.07220.21
5.6.70.0000.05720.17
5.6.60.0100.07320.41
5.6.50.0230.03720.42
5.6.40.0030.05020.13
5.6.30.0100.07320.18
5.6.20.0070.03920.36
5.6.10.0030.04420.39
5.6.00.0000.04720.17
5.5.380.0060.03817.64
5.5.370.0000.04217.63
5.5.360.0030.08617.55
5.5.350.0070.03817.66
5.5.340.0070.06317.84
5.5.330.0030.04418.01
5.5.320.0000.04717.75
5.5.310.0000.06917.84
5.5.300.0070.04017.74
5.5.290.0030.05118.13
5.5.280.0000.04418.03
5.5.270.0030.08818.09
5.5.260.0000.04418.05
5.5.250.0000.04617.88
5.5.240.0030.04717.48
5.5.230.0070.03717.23
5.5.220.0100.05617.12
5.5.210.0040.03917.38
5.5.200.0060.06517.19
5.5.190.0070.05617.19
5.5.180.0030.05017.47
5.5.160.0000.04217.44
5.5.150.0000.04517.52
5.5.140.0030.04417.52
5.5.130.0030.05417.47
5.5.120.0000.04217.38
5.5.110.0070.04317.44
5.5.100.0070.03617.00
5.5.90.0100.06317.00
5.5.80.0030.06817.11
5.5.70.0070.05717.42
5.5.60.0030.07517.33
5.5.50.0030.04816.98
5.5.40.0030.04217.33
5.5.30.0070.04117.27
5.5.20.0000.04117.27
5.5.10.0060.03917.29
5.5.00.0100.03917.27
5.4.450.0030.04019.41
5.4.440.0030.08319.39
5.4.430.0030.03819.46
5.4.420.0030.07519.32
5.4.410.0030.06619.36
5.4.400.0000.04119.25
5.4.390.0030.06819.16
5.4.380.0070.04019.08
5.4.370.0000.04219.15
5.4.360.0000.04619.12
5.4.350.0030.03719.17
5.4.340.0030.03818.98
5.4.320.0070.03618.93
5.4.310.0000.04118.97
5.4.300.0030.03919.08
5.4.290.0000.06419.13
5.4.280.0070.03718.95
5.4.270.0070.06518.94
5.4.260.0000.04618.98
5.4.250.0100.06119.13
5.4.240.0000.04019.05
5.4.230.0030.08118.89
5.4.220.0030.07519.06
5.4.210.0060.03619.23
5.4.200.0060.03518.98
5.4.190.0030.03919.21
5.4.180.0000.04118.96
5.4.170.0000.04418.88
5.4.160.0130.04419.06
5.4.150.0070.04019.16
5.4.140.0030.03716.65
5.4.130.0070.03016.65
5.4.120.0030.03616.54
5.4.110.0070.04016.80
5.4.100.0070.04316.54
5.4.90.0070.07216.54
5.4.80.0030.08016.70
5.4.70.0100.04016.64
5.4.60.0000.07316.75
5.4.50.0060.04816.60
5.4.40.0000.04116.51
5.4.30.0030.04916.68
5.4.20.0070.03416.46
5.4.10.0000.04416.55
5.4.00.0000.03816.21
5.3.290.0030.03715.31
5.3.280.0030.04015.31
5.3.270.0000.04615.31
5.3.260.0030.03615.31
5.3.250.0120.02815.31
5.3.240.0000.04215.31
5.3.230.0070.03415.31
5.3.220.0070.06215.31
5.3.210.0100.07115.31
5.3.200.0100.07315.31
5.3.190.0070.07315.31
5.3.180.0040.03615.31
5.3.170.0030.03715.31
5.3.160.0070.03215.31
5.3.150.0070.03215.31
5.3.140.0070.03715.31
5.3.130.0000.04815.31
5.3.120.0070.03615.31
5.3.110.0030.04315.31
5.3.100.0060.03515.31
5.3.90.0070.03715.31
5.3.80.0070.03315.31
5.3.70.0000.04315.31
5.3.60.0100.03215.31
5.3.50.0170.04215.31
5.3.40.0000.04215.31
5.3.30.0030.07315.31
5.3.20.0030.03315.31
5.3.10.0000.03615.31
5.3.00.0060.03215.31
5.2.170.0030.02715.31
5.2.160.0130.02515.31
5.2.150.0000.03015.31
5.2.140.0070.04615.31
5.2.130.0060.02615.31
5.2.120.0030.02715.31
5.2.110.0000.03015.31
5.2.100.0000.03115.31
5.2.90.0040.02915.31
5.2.80.0030.03115.31
5.2.70.0070.05115.31
5.2.60.0030.03315.31
5.2.50.0030.02715.31
5.2.40.0070.02415.31
5.2.30.0070.04915.31
5.2.20.0000.03315.31
5.2.10.0000.03215.31
5.2.00.0030.02715.31
5.1.60.0030.02415.31
5.1.50.0030.02615.31
5.1.40.0000.02815.31
5.1.30.0000.02915.31
5.1.20.0000.02815.31
5.1.10.0100.02315.31
5.1.00.0000.03115.31
5.0.50.0000.02715.31
5.0.40.0000.02415.31
5.0.30.0030.03115.31
5.0.20.0000.02115.31
5.0.10.0030.01715.31
5.0.00.0070.03215.31
4.4.90.0000.01715.31
4.4.80.0000.01915.31
4.4.70.0000.01715.31
4.4.60.0060.01115.31
4.4.50.0030.02915.31
4.4.40.0060.02215.31
4.4.30.0070.01015.31
4.4.20.0000.01715.31
4.4.10.0060.01515.31
4.4.00.0000.02615.31
4.3.110.0000.02415.31
4.3.100.0000.02315.31
4.3.90.0060.01215.31
4.3.80.0030.02315.31
4.3.70.0000.01615.31
4.3.60.0030.01415.31
4.3.50.0030.01315.31
4.3.40.0000.02715.31
4.3.30.0040.02215.31
4.3.20.0040.01515.31
4.3.10.0000.01715.31
4.3.00.0070.01315.31

preferences:
40.41 ms | 401 KiB | 5 Q