3v4l.org

run code in 300+ PHP versions simultaneously
<?php function find_pairs($array) { // re-index to 0 $array = array_values($array['parent_id']); // sort so the longest arrays are first usort($array, function ($a, $b) { return count($b) - count($a); }); // output array $pairs = array(); $c = count($array); $i = 0; // loop while there are enough values to pair (2 or more) while (array_reduce($array, function ($c, $v) { return $c + count($v); }, 0) > 1) { // make sure there are some elements in this array while (!count($array[$i])) $i = ($i + 1) % $c; // find the next array with a value $j = ($i + 1) % $c; while (!count($array[$j])) $j = ($j + 1) % $c; // have we come full circle? if ($j == $i) break; // save the pair $pairs[] = array(array_shift($array[$i]), array_shift($array[$j])); // move on to the next array $i = ($i + 1) % $c; } return $pairs; } $array = array ('parent_id' => array([1])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1], [3])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1], [3], [5])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1], [3], [5], [7])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2], [3])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2], [3], [5])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2], [3], [5], [7])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2], [3, 4])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2], [3, 4], [5])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2], [3, 4], [5], [7])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2], [3, 4], [5, 6])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2], [3, 4], [5, 6], [7])); print_r(find_pairs($array)); $array = array ('parent_id' => array([1, 2], [3, 4], [5, 6], [7, 8])); print_r(find_pairs($array));

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)
8.4.130.0120.00519.56
8.4.120.0140.00520.66
8.4.110.0110.00922.71
8.4.100.0150.00617.59
8.4.90.0070.01220.59
8.4.80.0070.00318.71
8.4.70.0090.00918.88
8.4.60.0140.00518.88
8.4.50.0070.01122.20
8.4.40.0130.00619.50
8.4.30.0090.00017.64
8.4.20.0050.00320.58
8.4.10.0130.00617.84
8.3.260.0100.01016.82
8.3.250.0120.00718.94
8.3.240.0090.00817.16
8.3.230.0060.00316.79
8.3.220.0110.00619.06
8.3.210.0040.00318.57
8.3.200.0050.00416.65
8.3.190.0090.00317.21
8.3.180.0130.00618.85
8.3.170.0150.00316.45
8.3.160.0000.00818.88
8.3.150.0150.00417.20
8.3.140.0040.01119.01
8.3.130.0100.01018.54
8.3.120.0030.00620.70
8.3.110.0000.01120.94
8.3.100.0000.01024.06
8.3.90.0130.00626.77
8.3.80.0060.00316.75
8.3.70.0080.00816.75
8.3.60.0220.00916.88
8.3.50.0150.00419.37
8.3.40.0040.01218.75
8.3.30.0130.00318.70
8.3.20.0030.00521.02
8.3.10.0110.00723.71
8.3.00.0000.00821.74
8.2.290.0100.00820.80
8.2.280.0110.00918.32
8.2.270.0120.00618.94
8.2.260.0060.01216.84
8.2.250.0120.00316.80
8.2.240.0000.00819.04
8.2.230.0030.00722.58
8.2.220.0090.00937.54
8.2.210.0030.00626.77
8.2.200.0090.00017.00
8.2.190.0150.00016.88
8.2.180.0070.01116.63
8.2.170.0070.01122.96
8.2.160.0140.00022.96
8.2.150.0060.00324.18
8.2.140.0110.00724.66
8.2.130.0030.00519.83
8.2.120.0090.00926.35
8.2.110.0070.00419.27
8.2.100.0110.00017.91
8.2.90.0080.00017.75
8.2.80.0050.00418.82
8.2.70.0040.00417.75
8.2.60.0080.00018.16
8.2.50.0000.00818.10
8.2.40.0040.00419.46
8.2.30.0040.00420.57
8.2.20.0040.00418.07
8.2.10.0030.00619.52
8.2.00.0020.00518.21
8.1.330.0110.00822.36
8.1.320.0100.00917.98
8.1.310.0000.00816.72
8.1.300.0060.00317.92
8.1.290.0150.00318.88
8.1.280.0110.00425.92
8.1.270.0050.00322.14
8.1.260.0000.00826.35
8.1.250.0140.00328.09
8.1.240.0060.00322.65
8.1.230.0110.00017.71
8.1.220.0040.00417.74
8.1.210.0050.00318.77
8.1.200.0040.00417.23
8.1.190.0000.00817.35
8.1.180.0080.00018.10
8.1.170.0040.00418.65
8.1.160.0070.00018.92
8.1.150.0040.00418.98
8.1.140.0040.00419.07
8.1.130.0030.00320.20
8.1.120.0060.00317.40
8.1.110.0080.00017.48
8.1.100.0070.00017.54
8.1.90.0030.00517.49
8.1.80.0070.00317.40
8.1.70.0030.00517.41
8.1.60.0030.00517.55
8.1.50.0040.00417.55
8.1.40.0000.00917.60
8.1.30.0040.00817.66
8.1.20.0060.00617.69
8.1.10.0080.00017.60
8.1.00.0090.00017.55
8.0.300.0040.00418.88
8.0.290.0040.00416.88
8.0.280.0070.00018.40
8.0.270.0040.00417.18
8.0.260.0030.00318.54
8.0.250.0060.00317.07
8.0.240.0030.00317.04
8.0.230.0000.00717.05
8.0.220.0000.00716.90
8.0.210.0000.00716.93
8.0.200.0060.00017.04
8.0.190.0030.00516.93
8.0.180.0050.00317.01
8.0.170.0040.00416.84
8.0.160.0070.00316.98
8.0.150.0040.00416.93
8.0.140.0000.00716.95
8.0.130.0000.00613.41
8.0.120.0000.00716.80
8.0.110.0060.00316.93
8.0.100.0040.00416.82
8.0.90.0030.00616.84
8.0.80.0030.01216.91
8.0.70.0030.00617.00
8.0.60.0060.00316.77
8.0.50.0000.00817.04
8.0.30.0200.00316.81
8.0.20.0150.00717.18
8.0.10.0000.00817.09
8.0.00.0070.01416.71
7.4.330.0000.00516.77
7.4.320.0060.00016.70
7.4.300.0000.00716.70
7.4.290.0030.00316.64
7.4.280.0070.00016.55
7.4.270.0060.00316.56
7.4.260.0000.00816.68
7.4.250.0040.00416.49
7.4.240.0050.00316.70
7.4.230.0070.00016.74
7.4.220.0030.00516.35
7.4.210.0080.00816.63
7.4.200.0030.00616.71
7.4.160.0110.00616.56
7.4.140.0110.01117.86
7.4.130.0140.00716.54
7.4.120.0150.00416.54
7.4.110.0090.00916.68
7.4.100.0050.01316.57
7.4.90.0100.00616.58
7.4.80.0070.01019.39
7.4.70.0100.01016.72
7.4.60.0070.01016.29
7.4.50.0100.00616.41
7.4.40.0150.01216.50
7.4.00.0070.01015.02
7.3.330.0030.00313.44
7.3.320.0060.00013.39
7.3.310.0000.00716.39
7.3.300.0070.00016.43
7.3.290.0020.00516.43
7.3.280.0070.01016.36
7.3.260.0080.00916.43
7.3.240.0070.01016.58
7.3.230.0070.01616.54
7.3.210.0110.00716.38
7.3.200.0040.01316.25
7.3.190.0090.00916.50
7.3.180.0070.01016.65
7.3.170.0070.01016.63
7.3.160.0080.00816.41
7.3.40.0180.00414.81
7.3.30.0060.01914.82
7.3.20.0060.00916.48
7.3.10.0100.00316.68
7.3.00.0030.00916.80
7.2.330.0060.01216.73
7.2.320.0130.00616.73
7.2.310.0070.01116.90
7.2.300.0030.01416.88
7.2.290.0100.00716.69
7.2.170.0080.00514.94
7.2.160.0070.00714.96
7.2.150.0030.01016.65
7.2.140.0000.01416.72
7.2.130.0030.01016.77
7.2.120.0000.01417.02
7.2.110.0110.00316.97
7.2.100.0110.01116.93
7.2.90.0150.00616.83
7.2.80.0100.00316.79
7.2.70.0080.00816.82
7.2.60.0140.00716.84
7.2.50.0030.01216.69
7.2.40.0060.00616.71
7.2.30.0080.00416.84
7.2.20.0000.01316.91
7.2.10.0090.01316.97
7.2.00.0030.01016.84
7.1.280.0100.00315.74
7.1.270.0070.01115.58
7.1.260.0120.00415.53
7.1.250.0040.00915.82

preferences:
27.81 ms | 403 KiB | 5 Q