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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 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: Undefined array key 12 in /in/TBO5v on line 7 Warning: Undefined array key 43 in /in/TBO5v on line 7 Warning: Undefined array key 66 in /in/TBO5v on line 7 Warning: Undefined array key 21 in /in/TBO5v on line 7 Warning: Undefined array key 56 in /in/TBO5v on line 7 Warning: Undefined array key 78 in /in/TBO5v on line 7 Warning: Undefined array key 100 in /in/TBO5v on line 7 Duplicates count: 7Array ( [12] => 1 [43] => 6 [66] => 1 [21] => 2 [56] => 1 [78] => 2 [100] => 1 )
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 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined offset: 12 in /in/TBO5v on line 7 Notice: Undefined offset: 43 in /in/TBO5v on line 7 Notice: Undefined offset: 66 in /in/TBO5v on line 7 Notice: Undefined offset: 21 in /in/TBO5v on line 7 Notice: Undefined offset: 56 in /in/TBO5v on line 7 Notice: Undefined offset: 78 in /in/TBO5v on line 7 Notice: Undefined offset: 100 in /in/TBO5v on line 7 Duplicates count: 7Array ( [12] => 1 [43] => 6 [66] => 1 [21] => 2 [56] => 1 [78] => 2 [100] => 1 )
Output for 7.3.32 - 7.3.33
Duplicates count: 7Array ( [12] => 1 [43] => 6 [66] => 1 [21] => 2 [56] => 1 [78] => 2 [100] => 1 )

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