function sumup(){
var sum = 0;
if(!isNaN(parseInt(document.getElementById("field1").value))){
sum += parseInt(document.getElementById("field1").value);
};
if(!isNaN(parseInt(document.getElementById("field2").value))){
sum += parseInt(document.getElementById("field2").value);
};
if(!isNaN(parseInt(document.getElementById("field3").value))){
sum += parseInt(document.getElementById("field3").value);
};
if(!isNaN(parseInt(document.getElementById("field4").value))){
sum += parseInt(document.getElementById("field4").value);
};
if(!isNaN(parseInt(document.getElementById("field5").value))){
sum += parseInt(document.getElementById("field5").value);
};
if(!isNaN(parseInt(document.getElementById("field6").value))){
sum += parseInt(document.getElementById("field6").value);
};
if(!isNaN(parseInt(document.getElementById("field7").value))){
sum += parseInt(document.getElementById("field7").value);
};
if(!isNaN(parseInt(document.getElementById("field8").value))){
sum += parseInt(document.getElementById("field8").value);
};
if(!isNaN(parseInt(document.getElementById("field9").value))){
sum += parseInt(document.getElementById("field9").value);
};
if(!isNaN(parseInt(document.getElementById("field10").value))){
sum += parseInt(document.getElementById("field10").value);
};
if(!isNaN(parseInt(document.getElementById("field11").value))){
sum += parseInt(document.getElementById("field11").value);
};
if(!isNaN(parseInt(document.getElementById("field12").value))){
sum += parseInt(document.getElementById("field12").value);
};
if(!isNaN(parseInt(document.getElementById("field13").value))){
sum += parseInt(document.getElementById("field13").value);
};
if(!isNaN(parseInt(document.getElementById("field14").value))){
sum += parseInt(document.getElementById("field14").value);
};
if(!isNaN(parseInt(document.getElementById("field15").value))){
sum += parseInt(document.getElementById("field15").value);
};
if(!isNaN(parseInt(document.getElementById("field16").value))){
sum += parseInt(document.getElementById("field16").value);
};
if(!isNaN(parseInt(document.getElementById("field17").value))){
sum += parseInt(document.getElementById("field17").value);
};
if(!isNaN(parseInt(document.getElementById("field18").value))){
sum += parseInt(document.getElementById("field18").value);
};
if(!isNaN(parseInt(document.getElementById("field19").value))){
sum += parseInt(document.getElementById("field19").value);
};
if(!isNaN(parseInt(document.getElementById("field20").value))){
sum += parseInt(document.getElementById("field20").value);
};
if(!isNaN(parseInt(document.getElementById("field21").value))){
sum += parseInt(document.getElementById("field21").value);
};
if(!isNaN(parseInt(document.getElementById("field22").value))){
sum += parseInt(document.getElementById("field22").value);
};
if(!isNaN(parseInt(document.getElementById("field23").value))){
sum += parseInt(document.getElementById("field23").value);
};
if(!isNaN(parseInt(document.getElementById("field24").value))){
sum += parseInt(document.getElementById("field24").value);
};
if(!isNaN(parseInt(document.getElementById("field25").value))){
sum += parseInt(document.getElementById("field25").value);
};
if(!isNaN(parseInt(document.getElementById("field26").value))){
sum += parseInt(document.getElementById("field26").value);
};
if(!isNaN(parseInt(document.getElementById("field27").value))){
sum += parseInt(document.getElementById("field27").value);
};

document.getElementById("sum").innerHTML = sum;
};


<!--
function sumup_bo(){
var sum = 0;
if(!isNaN(parseInt(document.getElementById("field1").value))){
sum += parseInt(document.getElementById("field1").value);
};
if(!isNaN(parseInt(document.getElementById("field2").value))){
sum += parseInt(document.getElementById("field2").value);
};
if(!isNaN(parseInt(document.getElementById("field3").value))){
sum += parseInt(document.getElementById("field3").value);
};
if(!isNaN(parseInt(document.getElementById("field4").value))){
sum += parseInt(document.getElementById("field4").value);
};
if(!isNaN(parseInt(document.getElementById("field5").value))){
sum += parseInt(document.getElementById("field5").value);
};
if(!isNaN(parseInt(document.getElementById("field6").value))){
sum += parseInt(document.getElementById("field6").value);
};
if(!isNaN(parseInt(document.getElementById("field7").value))){
sum += parseInt(document.getElementById("field7").value);
};
if(!isNaN(parseInt(document.getElementById("field8").value))){
sum += parseInt(document.getElementById("field8").value);
};
if(!isNaN(parseInt(document.getElementById("field9").value))){
sum += parseInt(document.getElementById("field9").value);
};
if(!isNaN(parseInt(document.getElementById("field10").value))){
sum += parseInt(document.getElementById("field10").value);
};
if(!isNaN(parseInt(document.getElementById("field11").value))){
sum += parseInt(document.getElementById("field11").value);
};
if(!isNaN(parseInt(document.getElementById("field12").value))){
sum += parseInt(document.getElementById("field12").value);
};
if(!isNaN(parseInt(document.getElementById("field13").value))){
sum += parseInt(document.getElementById("field13").value);
};
if(!isNaN(parseInt(document.getElementById("field14").value))){
sum += parseInt(document.getElementById("field14").value);
};
if(!isNaN(parseInt(document.getElementById("field15").value))){
sum += parseInt(document.getElementById("field15").value);
};
if(!isNaN(parseInt(document.getElementById("field16").value))){
sum += parseInt(document.getElementById("field16").value);
};
if(!isNaN(parseInt(document.getElementById("field17").value))){
sum += parseInt(document.getElementById("field17").value);
};
if(!isNaN(parseInt(document.getElementById("field18").value))){
sum += parseInt(document.getElementById("field18").value);
};
if(!isNaN(parseInt(document.getElementById("field19").value))){
sum += parseInt(document.getElementById("field19").value);
};
if(!isNaN(parseInt(document.getElementById("field20").value))){
sum += parseInt(document.getElementById("field20").value);
};
if(!isNaN(parseInt(document.getElementById("field21").value))){
sum += parseInt(document.getElementById("field21").value);
};
if(!isNaN(parseInt(document.getElementById("field22").value))){
sum += parseInt(document.getElementById("field22").value);
};
if(!isNaN(parseInt(document.getElementById("field23").value))){
sum += parseInt(document.getElementById("field23").value);
};
if(!isNaN(parseInt(document.getElementById("field24").value))){
sum += parseInt(document.getElementById("field24").value);
};
if(!isNaN(parseInt(document.getElementById("field25").value))){
sum += parseInt(document.getElementById("field25").value);
};

document.getElementById("sum").innerHTML = sum;
};
//-->