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<?php $array = [ ["444", "0081"], ["449", "0081"], ["451", "0081"], ["455", "2100"], ["469", "2100"] ]; foreach ($array as $row) { if (!isset($result[$row[1]])) { $result[$row[1]] = $row; } else { $result[$row[1]][0] .= ',' . $row[0]; } } var_export(array_values($result));
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
array ( 0 => array ( 0 => '444,449,451', 1 => '0081', ), 1 => array ( 0 => '455,469', 1 => '2100', ), )
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/BhkIa on line 2
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/BhkIa on line 2
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/BhkIa on line 2
Process exited with code 255.

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