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<?php $input= array(12,43,66,21,56,43,43,78,78,100,43,43,43,21); $count_values = array(); foreach ($input as $a) { @$count_values[$a]++; } echo 'Duplicates count: '.count($count_values); print_r($count_values); ?>
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 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
Duplicates count: 7Array ( [12] => 1 [43] => 6 [66] => 1 [21] => 2 [56] => 1 [78] => 2 [100] => 1 )
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 Duplicates count: 7Array ( [12] => 1 [43] => 6 [66] => 1 [21] => 2 [56] => 1 [78] => 2 [100] => 1 )

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191.49 ms | 402 KiB | 291 Q