Adding dollar sign before each string in array?

Question

I have this string: $str = \"(he+is+genius*2)/clever\"; which looks like this in array;

Array ( 
  [0] => ( 
  [1] => he 
  [2] => + 
  [3]         


        

Answer 1

For each value, check if the first char (or the whole value) is made of characters with ctype_alpha, then prepend with $ :

// $arr is your array as defined in your question
foreach ($arr as &$val) {
 //OR if (ctype_alpha($val[0])) { 
 if (ctype_alpha($val)) {
   $val = '$' . $val;
 }
}

var_dump($arr);

Output :

array(6) {
  [0]=>
  string(3) "$he"
  [1]=>
  string(1) "+"
  [2]=>
  string(3) "$is"
  [3]=>
  string(1) "+"
  [4]=>
  string(7) "$genius"
  ...
}

Second solution, checking if it has a char at any position :

foreach ($arr as &$val) {
  $tmp = str_split($val); 
  foreach ($tmp as $char) {
    if (ctype_alpha($char)) {
      $val = '$' . $val;
      break;
    }
  } 
}