3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = "test"; $b = & $a; unset($a); echo $b;//输出什么 ?>

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)
8.3.40.0140.00318.54
8.3.30.0040.01118.49
8.3.20.0000.00718.70
8.3.10.0040.00420.97
8.3.00.0070.00021.73
8.2.170.0140.00322.96
8.2.160.0030.01320.52
8.2.150.0080.00024.18
8.2.140.0050.00324.66
8.2.130.0000.00826.16
8.2.120.0040.00421.00
8.2.110.0070.00320.35
8.2.100.0110.00017.72
8.2.90.0070.00019.08
8.2.80.0080.00017.97
8.2.70.0060.00317.38
8.2.60.0030.00617.93
8.2.50.0030.00618.07
8.2.40.0050.00218.22
8.2.30.0030.00521.16
8.2.20.0000.00817.67
8.2.10.0040.00417.66
8.2.00.0020.00517.75
8.1.270.0000.00723.99
8.1.260.0110.00326.35
8.1.250.0040.00428.09
8.1.240.0080.00420.64
8.1.230.0120.00020.88
8.1.220.0030.00518.77
8.1.210.0040.00418.88
8.1.200.0030.00617.23
8.1.190.0040.00417.41
8.1.180.0040.00418.10
8.1.170.0040.00418.32
8.1.160.0000.00818.71
8.1.150.0020.00518.67
8.1.140.0070.00017.29
8.1.130.0000.00717.73
8.1.120.0030.00517.35
8.1.110.0000.00717.26
8.1.100.0070.00017.41
8.1.90.0040.00417.27
8.1.80.0000.00717.31
8.1.70.0070.00017.36
8.1.60.0030.00517.39
8.1.50.0050.00217.46
8.1.40.0000.00717.32
8.1.30.0040.00417.55
8.1.20.0000.00817.66
8.1.10.0050.00317.39
8.1.00.0050.00317.28
8.0.300.0070.00020.05
8.0.290.0040.00417.05
8.0.280.0070.00018.39
8.0.270.0000.00817.16
8.0.260.0000.00716.71
8.0.250.0080.00017.01
8.0.240.0030.00616.95
8.0.230.0030.00316.78
8.0.220.0000.00716.84
8.0.210.0080.00016.75
8.0.200.0000.00616.89
8.0.190.0070.00016.91
8.0.180.0050.00316.79
8.0.170.0050.00516.82
8.0.160.0000.00716.89
8.0.150.0040.00416.74
8.0.140.0000.00816.66
8.0.130.0050.00013.28
8.0.120.0040.00416.89
8.0.110.0000.00716.68
8.0.100.0040.00416.87
8.0.90.0000.00816.90
8.0.80.0100.00716.84
8.0.70.0000.00716.79
8.0.60.0020.00516.84
8.0.50.0050.00216.82
8.0.30.0100.00817.03
8.0.20.0080.01017.40
8.0.10.0000.00716.71
8.0.00.0060.01416.65
7.4.330.0030.00316.69
7.4.320.0040.00416.56
7.4.300.0030.00316.32
7.4.290.0040.00416.49
7.4.280.0000.00816.48
7.4.270.0000.00716.48
7.4.260.0000.00613.19
7.4.250.0000.00816.45
7.4.240.0000.00716.32
7.4.230.0050.00216.36
7.4.220.0110.00616.58
7.4.210.0100.00516.58
7.4.200.0030.00316.58
7.4.190.0070.00016.41
7.4.160.0080.00816.25
7.4.150.0070.01117.40
7.4.140.0120.01217.86
7.4.130.0100.00716.41
7.4.120.0060.01516.55
7.4.110.0070.01016.44
7.4.100.0150.00616.38
7.4.90.0100.00716.51
7.4.80.0040.01219.39
7.4.70.0100.00716.39
7.4.60.0110.00916.42
7.4.50.0030.00616.16
7.4.40.0160.00022.77
7.4.30.0060.01016.44
7.4.10.0080.00914.75
7.4.00.0020.01414.96
7.3.330.0030.00313.06
7.3.320.0050.00013.17
7.3.310.0030.00416.23
7.3.300.0070.00016.09
7.3.290.0030.01616.19
7.3.280.0090.00616.17
7.3.270.0100.00617.40
7.3.260.0130.00918.24
7.3.250.0100.01016.44
7.3.240.0130.01016.27
7.3.230.0090.00916.50
7.3.210.0060.01016.40
7.3.200.0110.01119.39
7.3.190.0110.00616.52
7.3.180.0060.00916.43
7.3.170.0050.01116.31
7.3.160.0100.00616.47
7.3.130.0060.01214.66
7.3.120.0080.00614.73
7.3.110.0050.00914.84
7.3.100.0110.00514.86
7.3.90.0000.01514.71
7.3.80.0080.00614.60
7.3.70.0030.01014.73
7.3.60.0050.00714.70
7.3.50.0070.00514.71
7.3.40.0030.00814.74
7.3.30.0030.01014.83
7.3.20.0120.00216.65
7.3.10.0060.00716.43
7.3.00.0060.00716.46
7.2.330.0090.00816.54
7.2.320.0060.01216.58
7.2.310.0130.00616.56
7.2.300.0130.00316.52
7.2.290.0080.00816.54
7.2.260.0040.01115.17
7.2.250.0050.01115.00
7.2.240.0120.00514.86
7.2.230.0060.00614.61
7.2.220.0020.01314.66
7.2.210.0050.00714.85
7.2.200.0040.00814.86
7.2.190.0070.01114.91
7.2.180.0050.01014.82
7.2.170.0080.00514.92
7.2.160.0070.00714.83
7.2.150.0040.01416.78
7.2.140.0050.00816.75
7.2.130.0070.00716.73
7.2.120.0070.00716.74
7.2.110.0040.00816.83
7.2.100.0050.00716.78
7.2.90.0060.00616.87
7.2.80.0060.00916.73
7.2.70.0050.00716.79
7.2.60.0090.00716.76
7.2.50.0080.00816.60
7.2.40.0080.01016.65
7.2.30.0060.01116.75
7.2.20.0060.01016.81
7.2.10.0040.00716.78
7.2.00.0060.01017.38
7.1.330.0080.00615.66
7.1.320.0100.00215.69
7.1.310.0030.01215.41
7.1.300.0060.00815.50
7.1.290.0030.01215.61
7.1.280.0020.01115.56
7.1.270.0080.00515.48
7.1.260.0080.00715.64
7.1.250.0070.00815.59
7.1.240.0030.01215.75
7.1.230.0040.00715.78
7.1.220.0070.00315.61
7.1.210.0030.01415.79
7.1.200.0060.00315.77
7.1.190.0040.00715.75
7.1.180.0080.00415.66
7.1.170.0080.00015.77
7.1.160.0090.00615.61
7.1.150.0000.01415.86
7.1.140.0070.00715.67
7.1.130.0050.00515.83
7.1.120.0110.00415.85
7.1.110.0110.00015.82
7.1.100.0030.00916.84
7.1.90.0130.00015.75
7.1.80.0100.00315.82
7.1.70.0110.00516.43
7.1.60.0070.01117.51
7.1.50.0050.01416.25
7.1.40.0030.01015.65
7.1.30.0100.00015.75
7.1.20.0080.00015.73
7.1.10.0100.00615.54
7.1.00.0000.02419.18
7.0.330.0070.01015.42
7.0.320.0000.01315.14
7.0.310.0040.01115.34
7.0.300.0090.00615.43
7.0.290.0070.01015.29
7.0.280.0030.00715.35
7.0.270.0000.01415.25
7.0.260.0000.01415.37
7.0.250.0100.00315.52
7.0.240.0080.00415.26
7.0.230.0090.00315.15
7.0.220.0040.00415.11
7.0.210.0030.01315.36
7.0.200.0050.00816.04
7.0.190.0070.00415.44
7.0.180.0100.00315.51
7.0.170.0060.00615.38
7.0.160.0030.00915.35
7.0.150.0030.01015.16
7.0.140.0080.03718.72
7.0.130.0080.00015.41
7.0.120.0030.00615.41
7.0.110.0100.00315.28
7.0.100.0040.01215.18
7.0.90.0070.01015.42
7.0.80.0050.04717.75
7.0.70.0090.04217.73
7.0.60.0370.03717.71
7.0.50.0310.02717.69
7.0.40.0100.04016.76
7.0.30.0100.03716.72
7.0.20.0130.02016.55
7.0.10.0080.04316.76
7.0.00.0070.03416.79
5.6.400.0060.00914.37
5.6.390.0090.00614.36
5.6.380.0060.00614.58
5.6.370.0060.00314.11
5.6.360.0030.00914.38
5.6.350.0040.01114.55
5.6.340.0080.00414.18
5.6.330.0000.01014.26
5.6.320.0080.00414.17
5.6.310.0040.01114.20
5.6.300.0090.00314.27
5.6.290.0090.00614.52
5.6.280.0070.03617.63
5.6.270.0060.00914.20
5.6.260.0070.00714.11
5.6.250.0000.01614.27
5.6.240.0110.00014.19
5.6.230.0030.03617.41
5.6.220.0080.04117.50
5.6.210.0120.04017.37
5.6.200.0070.03517.61
5.6.190.0020.05217.61
5.6.180.0020.04617.55
5.6.170.0070.02317.56
5.6.160.0080.03317.61
5.6.150.0130.03517.64
5.6.140.0070.04617.51
5.6.130.0080.03517.71
5.6.120.0050.05017.57
5.6.110.0080.04517.63
5.6.100.0110.04017.67
5.6.90.0080.02517.53
5.6.80.0020.04817.17
5.6.70.0120.03717.26
5.6.60.0060.04317.24
5.6.50.0050.04717.14
5.6.40.0020.03517.27
5.6.30.0100.04017.17
5.6.20.0100.04417.21
5.6.10.0130.03717.35
5.6.00.0020.03417.27
5.5.380.0030.00714.29
5.5.370.0090.04717.33
5.5.360.0080.03817.32
5.5.350.0060.04017.32
5.5.340.0050.04417.37
5.5.330.0070.04817.46
5.5.320.0030.03017.54
5.5.310.0080.03317.60
5.5.300.0100.04217.37
5.5.290.0050.05217.60
5.5.280.0030.04517.49
5.5.270.0080.04217.43
5.5.260.0100.03617.47
5.5.250.0030.04217.35
5.5.240.0080.04016.95
5.5.230.0030.04117.06
5.5.220.0130.03717.01
5.5.210.0090.02617.07
5.5.200.0100.02817.12
5.5.190.0100.04017.21
5.5.180.0050.04817.20
5.5.170.0000.01314.24
5.5.160.0070.04017.21
5.5.150.0080.04017.08
5.5.140.0040.04617.28
5.5.130.0030.04317.19
5.5.120.0090.04017.02
5.5.110.0050.02817.22
5.5.100.0080.03717.20
5.5.90.0070.04216.95
5.5.80.0070.04417.07
5.5.70.0020.03616.94
5.5.60.0030.04017.12
5.5.50.0110.03217.12
5.5.40.0110.03616.89
5.5.30.0070.04117.12
5.5.20.0010.02717.06
5.5.10.0050.02317.14
5.5.00.0030.04516.89
5.4.450.0050.03615.66
5.4.440.0000.03315.56
5.4.430.0120.03915.74
5.4.420.0030.02715.56
5.4.410.0080.01815.71
5.4.400.0060.04215.56
5.4.390.0050.04315.56
5.4.380.0050.04215.57
5.4.370.0050.03815.49
5.4.360.0100.03315.47
5.4.350.0100.03815.53
5.4.340.0030.04915.57
5.4.330.0000.01012.00
5.4.320.0090.02615.49
5.4.310.0050.04015.62
5.4.300.0060.04115.53
5.4.290.0050.04515.57
5.4.280.0090.02715.39
5.4.270.0050.03815.51
5.4.260.0020.03515.57
5.4.250.0050.04115.57
5.4.240.0090.03215.48
5.4.230.0030.03015.62
5.4.220.0090.03015.53
5.4.210.0050.04315.47
5.4.200.0080.03815.53
5.4.190.0070.03815.54
5.4.180.0020.03215.53
5.4.170.0050.04015.53
5.4.160.0070.03915.47
5.4.150.0100.03815.56
5.4.140.0050.03014.15
5.4.130.0070.03514.19
5.4.120.0060.02814.18
5.4.110.0050.03814.22
5.4.100.0000.03514.21
5.4.90.0050.03014.13
5.4.80.0130.03114.20
5.4.70.0050.04014.21
5.4.60.0050.04014.09
5.4.50.0080.03714.20
5.4.40.0020.02714.12
5.4.30.0060.02014.14
5.4.20.0020.02614.20
5.4.10.0120.01714.21
5.4.00.0070.03713.86
5.3.290.0080.04113.26
5.3.280.0030.04213.28
5.3.270.0020.02513.30
5.3.260.0060.04013.25
5.3.250.0080.03513.28
5.3.240.0000.04313.29
5.3.230.0080.03013.30
5.3.220.0020.03013.19
5.3.210.0050.03313.21
5.3.200.0060.04113.26
5.3.190.0020.04313.27
5.3.180.0060.03813.21
5.3.170.0050.03913.27
5.3.160.0090.03813.20
5.3.150.0020.03113.26
5.3.140.0080.03713.27
5.3.130.0030.02213.24
5.3.120.0050.02313.25
5.3.110.0000.02613.25
5.3.100.0030.04112.95
5.3.90.0080.02712.92
5.3.80.0040.02413.00
5.3.70.0100.02512.94
5.3.60.0050.02812.97
5.3.50.0050.04012.89
5.3.40.0030.03612.95
5.3.30.0020.04312.95
5.3.20.0080.03712.73
5.3.10.0040.03712.82
5.3.00.0080.03812.77
5.2.170.0100.06012.93
5.2.160.0100.04312.93
5.2.150.0070.06712.93
5.2.140.0070.05312.93
5.2.130.0070.06012.93
5.2.120.0030.06012.93
5.2.110.0030.04312.93
5.2.100.0100.05712.93
5.2.90.0070.05312.93
5.2.80.0000.04012.93
5.2.70.0100.03712.93
5.2.60.0100.06012.93
5.2.50.0030.06312.93
5.2.40.0000.05712.93
5.2.30.0030.06712.93
5.2.20.0070.05712.93
5.2.10.0070.06012.93
5.2.00.0070.05312.93
5.1.60.0030.05712.93
5.1.50.0070.05012.93
5.1.40.0000.05312.93
5.1.30.0100.04712.93
5.1.20.0030.04312.93
5.1.10.0070.05312.93
5.1.00.0070.05012.93
5.0.50.0030.04712.93
5.0.40.0030.05312.93
5.0.30.0000.06012.93
5.0.20.0000.04712.93
5.0.10.0030.02312.93
5.0.00.0070.06012.93
4.4.90.0030.03312.93
4.4.80.0030.03312.93
4.4.70.0030.03312.93
4.4.60.0070.02712.93
4.4.50.0070.03012.93
4.4.40.0070.05312.93
4.4.30.0000.03712.93
4.4.20.0100.03012.93
4.4.10.0030.03712.93
4.4.00.0070.05012.93
4.3.110.0030.03712.93
4.3.100.0070.03012.93
4.3.90.0030.01712.93
4.3.80.0070.05012.93
4.3.70.0030.03312.93
4.3.60.0000.03312.93
4.3.50.0000.03312.93
4.3.40.0000.03012.93
4.3.30.0000.02312.93
4.3.20.0000.02012.93
4.3.10.0030.03312.93
4.3.00.0000.02312.93

preferences:
46.57 ms | 400 KiB | 5 Q