Description:
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Hi,

This is my code:

<?php

  $chemString = "H2O,3PO4.12WO3.XH2O,6H4(CH3)2,5H10O5";
  $chemString = trim($chemString);
  $offset = 0;
  $tempStr = "";

  for ($k=0;$k<mb_strlen($chemString);$k++){
      if ($k>0 && is_numeric(mb_substr($chemString,$k,1))){
          if (preg_match("/^[A-Z]+$/",mb_substr($chemString,$k-1,1))){
             $tempStr .= substr($chemString,$offset,1);
             $tempStr .= "<sub>".substr($chemString,$offset+1,1)."</sub>";
             $offset = $offset+3;
             echo "ggg".strlen($offset)."sss<br />";
          }
      }
        echo "<br />".$k;
  }

?>

This is the source:

<br />0ggg1sss<br /><br />1<br />2<br />3<br />4<br />5<br />6ggg1sss<br /><br />7<br />8<br />9<br />10<br />11<br />12ggg1sss<br /><br />13<br />14<br />15<br />16ggg2sss<br /><br />17<br />18<br />19<br />20<br />21ggg2sss<br /><br />22<br />23<br />24<br />25ggg2sss<br /><br />26<br />27<br />28<br />29<br />30<br />31ggg2sss<br /><br />32<br />33<br />34ggg2sss<br /><br />35

Expected result:
----------------
There is an extra <br /> tag. I know it's hard to see, but looks like a bug.


i.e "<br />0ggg1sss<br /><br />1<br />"  --- the <br /> in the middle came from nowhere!!