返回匹配数组键的最大值

Question

How would I obtain the greatest value in an array if one of the array keys match a value in a string. For instance, the following results would be obtained.

  $decenders=array('Q'=>4,'g'=>4,'j'=>5,'p'=>4,'q'=>4,'y'=>4);
  $string='ABC';    //results as 0
  $string='ABCg';   //results as 4
  $string='ABCgj';  //results as 5

Answer 1

I think easiest way (but not quickest) is to do like:

$decenders= array('Q'=>4,'g'=>4,'j'=>5,'p'=>4,'q'=>9,'y'=>4);
$sData    = 'ABqC';

arsort($decenders);
$rgResult = array_intersect(array_keys($decenders), str_split($sData));
$iResult  = count($rgResult)?$decenders[array_shift($rgResult)]:0;
//var_dump($iResult); //9