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<?php $arr = [ [[58 => 32]], [[58 => 34]], [[57 => 26]], [[57 => 27]], [[56 => 16]], [[56 => 17]] ]; array_walk_recursive($arr, function($v,$k) use (&$r){ $r[$k] = isset($r[$k]) ? ($r[$k]+$v) : $v; }); print_r($r);
Output for 7.2.0 - 7.2.33, 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 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
Array ( [58] => 66 [57] => 53 [56] => 33 )
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 ( [58] => 66 [57] => 53 [56] => 33 )

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157.24 ms | 402 KiB | 182 Q