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<?php $array = array("a1" => 0, "a2" => 2, "a3" => 1, "b1" => 2, "b2" => 3); $final_array=[]; foreach($array as $key=>$value){ $final_array[$key[0]] = (isset($final_array[$key[0]])) ? $final_array[$key[0]]+$value : $value; } print_r($final_array);
Output for 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 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Array ( [a] => 3 [b] => 5 )
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78.1 ms | 1810 KiB | 4 Q