How PHP sets the key for array to equal to value

How PHP sets the key of an array to equal to value
Has the following array
Array ([0] = = content 1 [1] = content 2 [2] = = Content 3)

The following arrays are expected to be processed

Array ("Content 1" = "Content 1", "Content 2" + "Content 2", "Content 3" and "Content 3")

------Solution--------------------
foreach iterates through the array, and then uses the For loop to loop the value of key.
------Solution--------------------

PHP Code

$arr =array (0 = ' content 1 ', 1 = ' content 2 ', 2 = ' content 3 '), foreach ($arr as $v) $k []= $v;p Rint_r (Array_combine ($k, $arr));
------Solution--------------------

  
  
  

   
   
   PHP Code
   
   
   
$arr = Array (0 = ' content 1 ', 1 = ' content 2 ', 2 = ' content 3 '), $r = Array_combine (Array_values ($arr), $arr);p Rint_r ($r);
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