PHP. Replace negative elements in the mass with positive elements

Dun mass M (20). Create a program that transforms the negative elements of this body into positive.

Evolution of the code in php research
Yes.$m = [1,1,...];
termination 1
for($i = 0; $i < count($m); $i++){ if($m[$i] < 0){ $m[i] = $m[$i]; } }
termination 2
$len = count($m); for($i = 0; $i < $len; $i++){ .... }
terrain 2.1
$n = count($m); while($n){ $m[$n] = .... }
termination 3
foreach($m as $idx => $v){ if($v < 0) $m[$idx] = $v; }
Fourth
foreach($m as &$v){ if($v < 0 ) $v = $v; }
Five. One.
foreach($m as &$v){ $v = $v < 0 ? $v : $v; }
Five. Two.
foreach($m as &$v){ $v = $v * ($v < 0 ? 1 : 1); }
Six.
foreach($m as &$v) $v = abs($v);
Seven.
array_walk($m, function(&$v){ $v = abs($v); });
eight.
$m = array_map(function($v){ return abs($v); }, $m);
eight. One.
$m = array_map($fn($v) => abs($v), $m);
9
$m = array_map('abs', $m);