PHP version of arbitrary hexadecimal conversion

  $int=36;  $str=array();  $flag=0;  //echo chr($int %36+87);  while($int!=0)  {  if($int%36<=9)$str[$flag++]=$int%36;//36 hexadecimal  else $str[ $flag++]=chr($int%36+87);  $int/=36;  }  for($i=$flag;$i>=0;$i-=1)if($str[$ i]!=0)break;//There are some flaws in the output here. I hope someone can give me some advice (no output when $int=360) 
 for(;$i>=0;$i-=1)echo $str[$ i]; 
 //echo $str; 
 ?>

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