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<?php $arr = ["a", "b", "c", "d", "e", "f"]; foreach($arr as $k => $v) $arr[$k] = ["current" => $v, "next" => ""]; foreach($arr as $k => $v) { if(isset($arr[$k+1])) $arr[$k]["next"] = &$arr[$k+1]["current"]; else $arr[$k]["next"] = ""; } print_r($arr); $arr[1]["current"] = "c"; print_r($arr);
Output for 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
Array ( [0] => Array ( [current] => a [next] => b ) [1] => Array ( [current] => b [next] => c ) [2] => Array ( [current] => c [next] => d ) [3] => Array ( [current] => d [next] => e ) [4] => Array ( [current] => e [next] => f ) [5] => Array ( [current] => f [next] => ) ) Array ( [0] => Array ( [current] => a [next] => c ) [1] => Array ( [current] => c [next] => c ) [2] => Array ( [current] => c [next] => d ) [3] => Array ( [current] => d [next] => e ) [4] => Array ( [current] => e [next] => f ) [5] => Array ( [current] => f [next] => ) )
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 Array ( [0] => Array ( [current] => a [next] => b ) [1] => Array ( [current] => b [next] => c ) [2] => Array ( [current] => c [next] => d ) [3] => Array ( [current] => d [next] => e ) [4] => Array ( [current] => e [next] => f ) [5] => Array ( [current] => f [next] => ) ) Array ( [0] => Array ( [current] => a [next] => c ) [1] => Array ( [current] => c [next] => c ) [2] => Array ( [current] => c [next] => d ) [3] => Array ( [current] => d [next] => e ) [4] => Array ( [current] => e [next] => f ) [5] => Array ( [current] => f [next] => ) )

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