问Javascript在将数字相加时删除小数

EN

<form class="weight_form" data-ajax="false" method="post">
<input type="text" class="input_save" placeholder="save as.."/>
<input type="text" id="lf" placeholder="enter LF lbs" value="" onkeyup="myFunction()"/>
<input type="text" id="rf" placeholder="enter RF lbs" value="" onkeyup="myFunction()"/>
<input type="text" id="lr" placeholder="enter LR lbs" value="" onkeyup="myFunction()"/>
<input type="text" id="rr" placeholder="enter RR lbs" value="" onkeyup="myFunction()"/>
<input type="submit" id="sub_save" value="save"/>

<div id="bottom_section">
    <input type="text" id="total"  value=""/>
    <input type="text" id="cross"  value=""/>
    <input type="text" id="ls"  value=""/>
    <input type="text" id="bite"  value=""/>    
</div>

<script>
function myFunction() {
var lf = document.getElementById("lf");
var rf = document.getElementById("rf");
var lr = document.getElementById("lr");
var rr = document.getElementById("rr");

var lf = parseInt(lf.value);
var rf = parseInt(rf.value);
var lr = parseInt(lr.value);
var rr = parseInt(rr.value);

  var lf_1 = lf*1;
  var rf_1 = rf*1;
  var lr_1 = lr*1;
  var rr_1 = rr*1;

  var total = lf_1 + rf_1 + lr_1 + rr_1;
  var cross = rf_1 + lr_1 / total;
  var ls = lf_1 + lr_1 / total;
  var bite = lr_1 - rr_1;


$('#total').val(total);
$('#cross').val(Math.round(cross));
$('#ls').val(Math.round(ls));
$('#bite').val(bite);
};
</script>