Ciao a tutti,

vorrei modificare uno script trovato in questo form e adattarlo alle mie esigenze:

codice:
<script type="text/javascript">
		
	function SommaD(Sel){
	var TotaleD = parseInt(document.getElementById("totD").value)
	var sommaD = parseInt(TotaleD)+parseInt(Sel)
	document.getElementById("totD").value=sommaD
	}
	function SommaT(Sel){
	var TotaleT = parseInt(document.getElementById("totT").value)
	var sommaT = parseInt(TotaleT)+parseInt(Sel)
	document.getElementById("totT").value=sommaT
	}
	function SommaQ(Sel){
	var TotaleQ = parseInt(document.getElementById("totQ").value)
	var sommaQ = parseInt(TotaleQ)+parseInt(Sel)
	document.getElementById("totQ").value=sommaQ
	}
    </script>    
<form action="f1" method="get">
  <select name="select1" id="select1" onchange="SommaD(this.options[this.selectedIndex].value)">
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
    <option value="5">5</option>
    <option value="6">6</option>
    <option value="7">7</option>
    <option value="8">8</option>
  </select>
  <select name="select2" id="select2" onchange="SommaD(this.options[this.selectedIndex].value)">
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
    <option value="5">5</option>
    <option value="6">6</option>
    <option value="7">7</option>
    <option value="8">8</option>
  </select>
  <input name="totD" type="text" id="totD" value="0" />

  


  <select name="select3" id="select3" onchange="SommaT(this.options[this.selectedIndex].value)">
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
    <option value="5">5</option>
    <option value="6">6</option>
    <option value="7">7</option>
    <option value="8">8</option>
  </select>
  <select name="select4" id="select4" onchange="SommaT(this.options[this.selectedIndex].value)">
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
    <option value="5">5</option>
    <option value="6">6</option>
    <option value="7">7</option>
    <option value="8">8</option>
  </select>
  <input name="totT" type="text" id="totT" value="0" />

  


  <select name="select5" id="select5" onchange="SommaQ(this.options[this.selectedIndex].value)">
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
    <option value="5">5</option>
    <option value="6">6</option>
    <option value="7">7</option>
    <option value="8">8</option>
  </select>
  <select name="select6" id="select6" onchange="SommaQ(this.options[this.selectedIndex].value)">
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
    <option value="5">5</option>
    <option value="6">6</option>
    <option value="7">7</option>
    <option value="8">8</option>
  </select>
  <input name="totQ" type="text" id="totQ" value="0" />  

</form>
in pratica lo script somma le varie select suddivise per gruppo (sommaD, sommaT e sommaQ).
la mia esigenza è quella di aggiungere un campo dove inserire il totale di queste somme(totD+totT+totQ)