3v4l.org

run code in 300+ PHP versions simultaneously
<?php function longest_palendrome($string) { $current = $longest = ''; foreach (str_split(strrev($string)) as $char) { if (strstr($string, $current . $char)) { $current .= $char; } elseif (!empty($current) && strlen($current) > strlen($longest)) { $longest = $current; $current = ''; } } return $longest; } echo longest_palendrome("i ama racecar");

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)
8.3.60.0110.00418.27
8.3.50.0110.01018.29
8.3.40.0160.00318.67
8.3.30.0070.00718.59
8.3.20.0080.00018.65
8.3.10.0040.00418.78
8.3.00.0080.00019.38
8.2.180.0100.01016.50
8.2.170.0100.01022.96
8.2.160.0140.00018.76
8.2.150.0090.00024.18
8.2.140.0080.00024.66
8.2.130.0070.00026.16
8.2.120.0040.00419.79
8.2.110.0130.00720.90
8.2.100.0090.00317.84
8.2.90.0060.00618.34
8.2.80.0000.00817.97
8.2.70.0080.00017.50
8.2.60.0000.00718.16
8.2.50.0040.00418.07
8.2.40.0080.00019.38
8.2.30.0030.00717.74
8.2.20.0000.01117.55
8.2.10.0080.00019.60
8.2.00.0000.00717.75
8.1.280.0070.00725.92
8.1.270.0030.00523.99
8.1.260.0080.00026.35
8.1.250.0050.00328.09
8.1.240.0060.00322.64
8.1.230.0030.00721.04
8.1.220.0030.00517.74
8.1.210.0040.00418.90
8.1.200.0060.00317.00
8.1.190.0070.00317.00
8.1.180.0060.00318.10
8.1.170.0000.00718.89
8.1.160.0000.00718.96
8.1.150.0030.00518.62
8.1.140.0000.00717.35
8.1.130.0000.00719.19
8.1.120.0050.00317.37
8.1.110.0070.00017.32
8.1.100.0070.00017.33
8.1.90.0070.00017.46
8.1.80.0020.00517.32
8.1.70.0040.00417.36
8.1.60.0070.00017.59
8.1.50.0080.00017.49
8.1.40.0060.00317.53
8.1.30.0000.00917.53
8.1.20.0070.00317.60
8.1.10.0040.00417.46
8.1.00.0060.00317.44
8.0.300.0040.00419.98
8.0.290.0040.00416.75
8.0.280.0070.00018.43
8.0.270.0030.00317.30
8.0.260.0030.00316.73
8.0.250.0040.00416.84
8.0.240.0000.00716.90
8.0.230.0040.00416.89
8.0.220.0000.00716.79
8.0.210.0060.00016.84
8.0.200.0070.00016.95
8.0.190.0030.00417.00
8.0.180.0040.00416.76
8.0.170.0000.00816.89
8.0.160.0030.00316.91
8.0.150.0040.00416.73
8.0.140.0040.00416.77
8.0.130.0000.00513.35
8.0.120.0030.00716.82
8.0.110.0040.00416.87
8.0.100.0040.00416.75
8.0.90.0000.00716.85
8.0.80.0080.00816.76
8.0.70.0000.00716.80
8.0.60.0000.00916.91
8.0.50.0060.00316.76
8.0.30.0100.01017.10
8.0.20.0090.00917.06
8.0.10.0070.00016.90
8.0.00.0090.00916.72
7.4.330.0030.00213.04
7.4.320.0060.00016.58
7.4.300.0000.00716.50
7.4.290.0070.00316.55
7.4.280.0040.00416.42
7.4.270.0050.00316.52
7.4.260.0000.00613.14
7.4.250.0000.00816.34
7.4.240.0030.00316.49
7.4.230.0030.00316.31
7.4.220.0070.01516.56
7.4.210.0030.01416.63
7.4.200.0070.00016.69
7.4.190.0040.00416.38
7.4.160.0130.01016.44
7.4.150.0100.00716.38
7.4.140.0160.00617.86
7.4.130.0100.00716.38
7.4.120.0150.00416.43
7.4.110.0130.01216.54
7.4.100.0030.01316.48
7.4.90.0000.01716.49
7.4.80.0070.01019.39
7.4.70.0070.01116.38
7.4.60.0030.01316.44
7.4.50.0000.00816.45
7.4.40.0090.00916.57
7.4.30.0130.00416.65
7.4.00.0120.00514.73
7.3.330.0030.00313.20
7.3.320.0000.00613.14
7.3.310.0030.00316.45
7.3.300.0040.00416.17
7.3.290.0080.00616.33
7.3.280.0060.01316.41
7.3.270.0120.01316.52
7.3.260.0160.00416.43
7.3.240.0160.00616.61
7.3.230.0110.00716.45
7.3.210.0080.00816.50
7.3.200.0090.00916.49
7.3.190.0080.00816.42
7.3.180.0100.01016.38
7.3.170.0160.00716.39
7.3.160.0070.01416.64
7.3.120.0090.00714.90
7.3.110.0060.00615.02
7.3.100.0140.00314.80
7.3.90.0110.00714.79
7.3.80.0040.00714.68
7.3.70.0090.00314.89
7.3.60.0080.00814.63
7.3.50.0070.00414.86
7.3.40.0030.01014.96
7.3.30.0060.00914.91
7.3.20.0100.00316.76
7.3.10.0030.01016.49
7.3.00.0070.00316.75
7.2.330.0120.00616.63
7.2.320.0060.01716.67
7.2.310.0030.01416.45
7.2.300.0040.01816.53
7.2.290.0100.00716.86
7.2.250.0030.01615.02
7.2.240.0030.01814.71
7.2.230.0000.01514.89
7.2.220.0000.01014.74
7.2.210.0000.01114.93
7.2.200.0040.01115.21
7.2.190.0070.00714.96
7.2.180.0110.00415.01
7.2.170.0040.01114.85
7.2.00.0060.00619.43
7.1.330.0060.00615.92
7.1.320.0060.00615.55
7.1.310.0030.00915.55
7.1.300.0040.00715.47
7.1.290.0070.00315.75
7.1.280.0080.00415.79
7.1.270.0000.01615.89
7.1.260.0040.00815.66
7.1.100.0030.00718.18
7.1.70.0070.00017.25
7.1.60.0070.01719.25
7.1.50.0090.01516.84
7.1.00.0030.03322.40
7.0.200.0000.00716.46
7.0.140.0070.07021.95
7.0.120.0070.06722.18
7.0.60.0070.07719.94
7.0.50.0170.07017.87
7.0.40.0170.07320.27
7.0.30.0400.03320.24
7.0.20.0170.04320.07
7.0.10.0100.08020.11
7.0.00.0000.08320.18
5.6.280.0070.07020.90
5.6.210.0130.07320.50
5.6.200.0100.07718.29
5.6.190.0000.09020.41
5.6.180.0270.05720.48
5.6.170.0230.04020.57
5.6.160.0030.05720.55
5.6.150.0100.07718.15
5.6.140.0130.07018.16
5.6.130.0030.06718.10
5.6.120.0170.08020.90
5.6.110.0000.09721.02
5.6.100.0130.03320.96
5.6.90.0030.07720.98
5.6.80.0000.06020.38
5.6.70.4100.03320.38
5.5.350.0070.09020.45
5.5.340.0030.08317.99
5.5.330.0030.08720.21
5.5.320.0270.07720.35
5.5.310.0230.03720.39
5.5.300.0030.08018.13
5.5.290.0100.07718.04
5.5.280.0070.07020.90
5.5.270.0130.03320.77
5.5.260.0030.08720.78
5.5.250.0170.08320.68
5.5.240.0130.03320.15
5.4.450.0130.07719.48
5.4.440.0100.07319.41
5.4.430.0130.07319.24
5.4.420.0070.03719.29
5.4.410.0000.05019.35
5.4.400.0000.08018.98
5.4.390.0130.07318.99
5.4.380.0070.08019.12
5.4.370.0100.04019.15
5.4.360.0030.04719.12
5.4.350.0070.03719.08
5.4.340.0070.06019.24
5.4.320.0070.07719.15
5.4.310.0100.07319.14
5.4.300.0070.06019.11
5.4.290.0030.04318.92
5.4.280.0030.04019.14
5.4.270.0000.08319.02
5.4.260.0000.04319.20
5.4.250.0030.07019.08
5.4.240.0030.04018.87
5.4.230.0200.06719.13
5.4.220.0130.06719.11
5.4.210.0270.03018.91
5.4.200.0070.06019.23
5.4.190.0030.07719.23
5.4.180.0100.04718.84
5.4.170.0030.04019.25
5.4.160.0000.04018.83
5.4.150.0000.04718.82
5.4.140.0100.02716.46
5.4.130.0030.03716.29
5.4.120.0030.03316.49
5.4.110.0100.03316.39
5.4.100.0070.03316.37
5.4.90.0030.03716.40
5.4.80.0130.02316.37
5.4.70.0030.03316.32
5.4.60.0070.06316.34
5.4.50.0000.03716.43
5.4.40.0070.03316.36
5.4.30.0030.03316.27
5.4.20.0200.02716.44
5.4.10.0070.04016.27
5.4.00.0000.03715.75
5.3.290.0070.07714.71
5.3.280.0070.07714.65
5.3.270.0100.03314.75
5.3.260.0000.04014.60
5.3.250.0000.04014.65
5.3.240.0030.03314.62
5.3.230.0000.04014.75
5.3.220.0030.03714.71
5.3.210.0070.03314.57
5.3.200.0000.04014.64
5.3.190.0000.06014.73
5.3.180.0030.03714.57
5.3.170.0070.07014.71
5.3.160.0030.03714.61
5.3.150.0030.03314.56
5.3.140.0000.04014.55
5.3.130.0030.03714.61
5.3.120.0030.03714.54
5.3.110.0000.04314.59
5.3.100.0030.03714.06
5.3.90.0070.03314.05
5.3.80.0070.03014.04
5.3.70.0100.03014.07
5.3.60.0000.04013.95
5.3.50.0000.03713.89
5.3.40.0000.03714.11
5.3.30.0030.03313.96
5.3.20.0000.03713.69
5.3.10.0070.03013.62
5.3.00.0000.04313.68
5.2.170.0030.02711.22
5.2.160.0030.02711.19
5.2.150.0030.02711.14
5.2.140.0000.03011.15
5.2.130.0000.03011.02
5.2.120.0030.02711.09
5.2.110.0030.02710.98
5.2.100.0000.03011.15
5.2.90.0070.03011.05
5.2.80.0000.04311.06
5.2.70.0030.02711.09
5.2.60.0070.02710.94
5.2.50.0000.03011.18
5.2.40.0030.02710.94
5.2.30.0030.02711.00
5.2.20.0000.03310.98
5.2.10.0030.03010.90
5.2.00.0030.05010.77
5.1.60.0030.02710.06
5.1.50.0000.02710.00
5.1.40.0030.0239.96
5.1.30.0000.02710.30
5.1.20.0000.02710.32
5.1.10.0100.0409.97
5.1.00.0000.03710.07
5.0.50.0030.0308.52
5.0.40.0070.0438.36
5.0.30.0030.0678.24
5.0.20.0000.0438.24
5.0.10.0070.0408.22
5.0.00.0030.0478.30
4.4.90.0030.0137.79
4.4.80.0030.0137.79
4.4.70.0070.0137.79
4.4.60.0000.0177.79
4.4.50.0000.0437.79
4.4.40.0130.0177.79
4.4.30.0000.0177.79
4.4.20.0030.0137.79
4.4.10.0070.0307.79
4.4.00.0000.0337.79
4.3.110.0030.0177.79
4.3.100.0100.0277.79
4.3.90.0000.0207.79
4.3.80.0000.0277.79
4.3.70.0000.0377.79
4.3.60.0030.0237.79
4.3.50.0030.0207.79
4.3.40.0000.0407.79
4.3.30.0000.0207.79
4.3.20.0000.0407.79
4.3.10.0000.0307.79
4.3.00.0030.0177.79

preferences:
38.11 ms | 401 KiB | 5 Q