highlighting text temporarily by editing html content with javascript

$(document).ready(function (e) {
      $('#submit').click(function (e) {
          try {
              var $inputTxt = $('#search');
              result = $inputTxt.val();
              alert(result);


      $('p').each(function () {

          var a=$(this).html().toString();
          var aindx=[];

          while(a.indexOf(result) >= 0){

              //alert("string found "+a.indexOf(result)+" position");

              var b=a.substring((a.indexOf(result)+result.length));

              if(aindx.length > 0) {
                  var prev=aindx.length-1;
                  aindx[aindx.length]=a.indexOf(result)+aindx[prev];
                  $(this).html(a.substring(0,(aindx[aindx.length]-1))+'<mark id="tmprry">'+result+'</mark>'+a.substring(aindx[aindx.length+result.length-1]));
              } else {
                  aindx[0] =a.indexOf(result);
                  $(this).html(a.substring(0,(aindx[0]-1))+'<mark id="tmprry">'+result+'</mark>'+a.substring(aindx[0]));
              }

              //insert mark around position

              a=b;
          }


                  });



          } catch (ex) { e.preventDefault(); }
      });