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, $i).' '; echo '<br>3 letters from 4:\n'; for($i = 0; $i < getPermCount($letters, 3); $i++) echo getPerm($letters, 3, $i). " ";

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)
8.3.70.0110.00416.58
8.3.60.0130.00718.43
8.3.50.0120.00722.05
8.3.40.0040.01519.02
8.3.30.0070.00720.29
8.3.20.0060.00318.72
8.3.10.0070.00021.07
8.3.00.0050.00319.92
8.2.180.0090.00916.63
8.2.170.0060.01222.96
8.2.160.0000.01420.52
8.2.150.0000.00824.18
8.2.140.0040.00424.66
8.2.130.0040.00426.16
8.2.120.0000.00819.76
8.2.110.0030.00620.48
8.2.100.0040.00717.78
8.2.90.0040.00419.31
8.2.80.0050.00319.28
8.2.70.0040.00417.62
8.2.60.0080.00017.93
8.2.50.0040.00818.07
8.2.40.0000.00819.88
8.2.30.0040.00419.38
8.2.20.0040.00417.73
8.2.10.0060.00317.80
8.2.00.0030.00617.76
8.1.280.0100.00325.92
8.1.270.0030.00523.99
8.1.260.0080.00026.35
8.1.250.0080.00028.09
8.1.240.0030.00622.52
8.1.230.0040.00720.97
8.1.220.0050.00318.77
8.1.210.0030.00618.91
8.1.200.0080.00017.23
8.1.190.0000.00717.39
8.1.180.0080.00018.10
8.1.170.0040.00418.56
8.1.160.0040.00418.80
8.1.150.0000.00718.55
8.1.140.0070.00017.48
8.1.130.0050.00217.90
8.1.120.0000.01017.39
8.1.110.0050.00317.49
8.1.100.0040.00417.49
8.1.90.0070.00017.46
8.1.80.0000.00717.43
8.1.70.0000.00717.48
8.1.60.0030.00617.61
8.1.50.0040.00417.53
8.1.40.0030.00617.48
8.1.30.0000.00817.61
8.1.20.0000.00917.56
8.1.10.0030.00617.45
8.1.00.0000.00817.48
8.0.300.0040.00419.98
8.0.290.0050.00217.18
8.0.280.0040.00418.46
8.0.270.0030.00317.18
8.0.260.0030.00316.89
8.0.250.0040.00416.85
8.0.240.0000.00816.93
8.0.230.0070.00016.92
8.0.220.0000.00716.92
8.0.210.0030.00316.95
8.0.200.0030.00316.98
8.0.190.0040.00416.98
8.0.180.0040.00416.96
8.0.170.0080.00016.80
8.0.160.0000.00816.93
8.0.150.0030.00316.73
8.0.140.0000.00716.80
8.0.130.0000.00513.38
8.0.120.0060.00316.77
8.0.110.0030.00616.89
8.0.100.0000.00716.93
8.0.90.0000.00816.86
8.0.80.0090.00616.79
8.0.70.0040.00416.93
8.0.60.0070.00016.71
8.0.50.0000.00716.95
8.0.30.0090.01016.84
8.0.20.0100.01117.40
8.0.10.0040.00416.90
8.0.00.0130.00816.64
7.4.330.0060.00016.79
7.4.320.0000.00616.52
7.4.300.0030.00316.44
7.4.290.0030.00316.52
7.4.280.0030.00316.42
7.4.270.0000.00716.66
7.4.260.0030.00313.19
7.4.250.0030.00516.59
7.4.240.0070.00016.44
7.4.230.0000.00716.69
7.4.220.0130.01016.41
7.4.210.0050.00916.49
7.4.200.0000.00716.64
7.4.190.0070.00016.66
7.4.160.0170.00316.55
7.4.150.0140.00417.40
7.4.140.0240.01117.86
7.4.130.0090.01116.54
7.4.120.0140.00616.54
7.4.110.0120.01216.45
7.4.100.0090.01616.55
7.4.90.0060.01216.45
7.4.80.0090.00919.39
7.4.70.0140.00316.54
7.4.60.0100.00716.58
7.4.50.0040.00416.57
7.4.40.0090.00922.77
7.4.30.0080.00916.56
7.4.10.0090.00914.87
7.4.00.0090.00914.81
7.3.330.0000.00613.30
7.3.320.0030.00313.27
7.3.310.0050.00316.20
7.3.300.0030.00316.24
7.3.290.0060.00916.29
7.3.280.0070.00916.35
7.3.270.0210.00317.40
7.3.260.0140.00618.24
7.3.250.0110.00716.42
7.3.240.0130.00316.36
7.3.230.0120.00616.39
7.3.210.0030.01516.59
7.3.200.0090.01219.39
7.3.190.0090.00916.45
7.3.180.0130.00316.48
7.3.170.0060.00916.30
7.3.160.0110.00616.36
7.3.130.0110.00514.76
7.3.120.0060.00914.85
7.3.110.0060.01314.90
7.3.100.0050.00614.84
7.3.90.0050.00814.82
7.3.80.0060.00714.79
7.3.70.0070.00614.87
7.3.60.0020.01214.77
7.3.50.0050.00814.83
7.3.40.0040.01114.85
7.3.30.0060.00714.82
7.3.20.0040.01016.50
7.3.10.0080.00516.72
7.3.00.0060.00716.71
7.2.330.0090.00916.84
7.2.320.0130.01016.85
7.2.310.0060.01316.79
7.2.300.0140.00316.41
7.2.290.0080.00816.87
7.2.260.0060.01115.09
7.2.250.0070.01115.15
7.2.240.0070.01014.93
7.2.230.0040.01215.11
7.2.220.0060.00815.20
7.2.210.0030.00915.06
7.2.200.0050.01014.90
7.2.190.0080.00715.12
7.2.180.0030.01015.09
7.2.170.0040.01015.01
7.2.160.0110.00315.00
7.2.150.0020.01316.80
7.2.140.0030.00916.96
7.2.130.0110.00416.86
7.2.120.0090.00416.99
7.2.110.0070.00416.95
7.2.100.0100.00516.84
7.2.90.0080.00517.04
7.2.80.0040.00816.69
7.2.70.0050.00916.72
7.2.60.0050.01017.00
7.2.50.0040.01216.88
7.2.40.0050.01116.95
7.2.30.0100.00316.92
7.2.20.0100.00516.85
7.2.10.0050.01116.81
7.2.00.0070.00817.80
7.1.330.0070.00815.82
7.1.320.0060.00715.95
7.1.310.0050.00715.72
7.1.300.0090.00515.81
7.1.290.0050.00715.80
7.1.280.0100.00415.82
7.1.270.0070.00815.61
7.1.260.0060.00815.59
7.1.250.0060.00915.75
7.1.240.0010.00815.69
7.1.230.0060.00615.69
7.1.220.0030.01015.87
7.1.210.0030.00815.64
7.1.200.0080.00515.75
7.1.190.0060.00515.85
7.1.180.0080.00115.56
7.1.170.0050.01015.78
7.1.160.0030.01215.97
7.1.150.0060.00715.98
7.1.140.0060.00515.63
7.1.130.0100.00615.66
7.1.120.0050.00815.76
7.1.110.0040.00715.73
7.1.100.0020.01016.63
7.1.90.0080.00615.93
7.1.80.0060.00815.85
7.1.70.0040.00916.21
7.1.60.0020.01416.92
7.1.50.0090.00816.22
7.1.40.0060.00915.80
7.1.30.0060.00815.86
7.1.20.0030.00915.90
7.1.10.0050.00815.60
7.1.00.0060.01518.06
7.0.330.0070.00715.34
7.0.320.0080.00315.45
7.0.310.0070.00415.32
7.0.300.0050.00915.35
7.0.290.0050.00715.35
7.0.280.0040.00915.45
7.0.270.0030.00715.38
7.0.260.0050.00515.40
7.0.250.0040.00715.50
7.0.240.0070.00815.34
7.0.230.0060.00815.43
7.0.220.0090.00915.37
7.0.210.0060.00415.48
7.0.200.0060.00715.88
7.0.190.0060.00815.43
7.0.180.0030.01015.40
7.0.170.0030.01015.36
7.0.160.0030.00815.46
7.0.150.0050.00715.30
7.0.140.0010.03217.77
7.0.130.0060.00515.47
7.0.120.0070.00415.55
7.0.110.0100.00415.23
7.0.100.0120.02516.93
7.0.90.0050.02916.77
7.0.80.0080.02816.89
7.0.70.0070.02916.92
7.0.60.0100.02716.97
7.0.50.0070.02217.10
7.0.40.0070.02815.62
7.0.30.0070.02315.53
7.0.20.0070.02215.63
7.0.10.0050.03015.55
7.0.00.0090.03115.60
5.6.400.0070.01014.15
5.6.390.0040.00914.36
5.6.380.0070.00514.11
5.6.370.0050.00914.13
5.6.360.0030.00814.58
5.6.350.0030.00914.24
5.6.340.0030.01014.28
5.6.330.0050.00914.49
5.6.320.0060.00614.61
5.6.310.0050.01314.37
5.6.300.0070.00714.41
5.6.290.0040.00914.54
5.6.280.0070.02516.60
5.6.270.0070.00714.51
5.6.260.0110.00414.36
5.6.250.0020.03616.41
5.6.240.0030.03016.44
5.6.230.0050.02016.39
5.6.220.0050.01916.42
5.6.210.0060.02316.36
5.6.200.0050.03716.62
5.6.190.0080.03216.56
5.6.180.0100.03016.73
5.6.170.0060.03116.42
5.6.160.0120.02616.51
5.6.150.0100.02816.74
5.6.140.0060.03516.55
5.6.130.0100.03216.61
5.6.120.0070.03316.59
5.6.110.0070.03216.59
5.6.100.0080.03316.42
5.6.90.0010.02816.55
5.6.80.0120.02616.18
5.6.70.0060.02416.33
5.6.60.0060.03316.43
5.6.50.0040.02716.31
5.6.40.0010.02216.23
5.6.30.0080.03016.33
5.6.20.0040.03116.31
5.6.10.0100.02916.36
5.6.00.0050.03416.32
5.5.380.0030.02116.33
5.5.370.0110.02916.60
5.5.360.0070.02116.26
5.5.350.0050.02716.37
5.5.340.0050.03016.47
5.5.330.0070.03216.45
5.5.320.0090.02816.37
5.5.310.0100.02916.68
5.5.300.0090.02816.57
5.5.290.0030.03716.31
5.5.280.0080.03016.42
5.5.270.0050.03616.54
5.5.260.0040.03516.61
5.5.250.0060.03216.44
5.5.240.0100.02916.37
5.5.230.0070.03216.25
5.5.220.0070.02516.40
5.5.210.0070.03216.17
5.5.200.0070.03016.25
5.5.190.0060.03116.29
5.5.180.0040.03316.32
5.5.170.0070.00514.29
5.5.160.0070.03116.28
5.5.150.0100.02715.97
5.5.140.0060.03216.06
5.5.130.0060.03216.36
5.5.120.0070.03116.17
5.5.110.0090.02916.35
5.5.100.0090.02916.08
5.5.90.0090.02516.17
5.5.80.0010.03816.06
5.5.70.0100.02916.27
5.5.60.0090.01916.07
5.5.50.0060.03416.15
5.5.40.0090.03116.14
5.5.30.0080.02816.14
5.5.20.0120.02916.22
5.5.10.0090.03016.18
5.5.00.0070.03416.20
5.4.450.0070.03114.56
5.4.440.0130.02414.50
5.4.430.0060.02814.46
5.4.420.0080.02014.52
5.4.410.0090.02914.42
5.4.400.0060.02014.35
5.4.390.0070.02614.30
5.4.380.0050.01714.38
5.4.370.0030.03314.25
5.4.360.0100.02414.37
5.4.350.0100.02714.33
5.4.340.0120.02314.36
5.4.330.0020.00911.86
5.4.320.0060.03214.40
5.4.310.0050.02614.35
5.4.300.0050.01914.35
5.4.290.0050.02714.27
5.4.280.0100.02514.36
5.4.270.0060.02714.24
5.4.260.0010.03314.39
5.4.250.0060.02914.33
5.4.240.0080.02814.36
5.4.230.0020.02814.46
5.4.220.0030.02414.33
5.4.210.0060.02914.29
5.4.200.0040.03014.26
5.4.190.0070.02714.36
5.4.180.0020.03314.34
5.4.170.0050.03214.32
5.4.160.0090.02614.36
5.4.150.0060.02814.40
5.4.140.0050.02813.38
5.4.130.0090.02413.53
5.4.120.0110.02413.52
5.4.110.0050.02813.56
5.4.100.0090.02613.51
5.4.90.0020.03013.49
5.4.80.0020.02813.57
5.4.70.0090.02413.59
5.4.60.0070.02113.46
5.4.50.0050.02213.48
5.4.40.0040.02913.52
5.4.30.0080.01713.54
5.4.20.0030.03013.54
5.4.10.0080.01613.46
5.4.00.0050.03013.33
5.3.290.0080.02412.77
5.3.280.0050.01912.73
5.3.270.0080.02912.71
5.3.260.0040.03212.69
5.3.250.0040.02912.67
5.3.240.0070.03012.66
5.3.230.0050.03312.70
5.3.220.0000.03512.72
5.3.210.0050.03012.68
5.3.200.0050.03012.65
5.3.190.0060.01912.64
5.3.180.0060.02812.75
5.3.170.0030.02912.76
5.3.160.0090.02412.67
5.3.150.0060.03112.64
5.3.140.0040.03112.70
5.3.130.0100.02612.65
5.3.120.0080.02512.73
5.3.110.0070.02812.71
5.3.100.0030.02012.60
5.3.90.0030.02812.52
5.3.80.0040.02612.54
5.3.70.0030.03112.45
5.3.60.0070.02512.42
5.3.50.0050.02512.45
5.3.40.0060.02612.52
5.3.30.0040.02912.54
5.3.20.0060.02712.42
5.3.10.0040.03012.35
5.3.00.0060.02612.31
5.2.170.0100.05011.81
5.2.160.0000.06711.81
5.2.150.0030.06311.81
5.2.140.0030.05711.81
5.2.130.0100.06011.81
5.2.120.0100.05711.81
5.2.110.0170.03711.81
5.2.100.0000.05011.81
5.2.90.0030.06311.81
5.2.80.0070.06311.81
5.2.70.0070.06311.81
5.2.60.0030.06011.81
5.2.50.0000.04311.81
5.2.40.0070.05311.81
5.2.30.0030.04011.81
5.2.20.0130.05311.81
5.2.10.0100.05711.81
5.2.00.0070.06011.81
5.1.60.0070.02711.81
5.1.50.0130.04711.81
5.1.40.0070.05711.81
5.1.30.0000.04711.81
5.1.20.0030.05711.81
5.1.10.0070.05711.81
5.1.00.0030.03711.81
5.0.50.0030.05011.81
5.0.40.0030.04311.81
5.0.30.0070.06011.81
5.0.20.0170.03011.81
5.0.10.0030.04311.81
5.0.00.0030.06711.81
4.4.90.0030.03711.81
4.4.80.0000.02711.81
4.4.70.0030.03711.81
4.4.60.0070.03311.81
4.4.50.0000.04011.81
4.4.40.0030.04311.81
4.4.30.0030.03711.81
4.4.20.0070.03311.81
4.4.10.0030.03711.81
4.4.00.0030.02711.81
4.3.110.0070.03011.81
4.3.100.0070.02311.81
4.3.90.0030.03311.81
4.3.80.0030.05311.81
4.3.70.0030.03011.81
4.3.60.0030.03711.81
4.3.50.0000.02711.81
4.3.40.0070.05011.81
4.3.30.0000.03711.81
4.3.20.0000.03711.81
4.3.10.0030.03711.81
4.3.00.0030.03011.81

preferences:
63.61 ms | 401 KiB | 5 Q