<?php
 
function divideEtImpera($arr, $left, $right) {
 
         if($left == $right) {
 
            return $arr[ $left ];
 
         } else {
 
                $m = ($left + $right) >> 1;
                $a = divideEtImpera($arr, $left, $m);
                $b = divideEtImpera($arr, $m + 1, $right);
                if($a > $b) return $a;
                         else
                            return $b;
         }
 
}
 
$arr = array(10,20,2021,101,90,92,91,41);
 
$max = divideEtImpera($arr, 0, sizeof($arr));
 
echo$max;
 
?>

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