puoi anche risolvere senza dare id alle singole celle,
un esempio veloce
codice:
<script type="text/javascript">
function evidenzia(ww,hh){
if(document.getElementById && document.getElementsByTagName){
var t=document.getElementById('tabella');
var rr=t.getElementsByTagName('TR');
var c1="#ff0000"; // colore incontro
var c2="#00ff00"; // colore squadre
for(var r=0; r<=hh; r++){
for(var c=0; c<=ww; c++){
var cc=rr[r].getElementsByTagName('TD')[c];
if((c==0 && r==hh)||(c==ww && r==0)) cc.style.backgroundColor=c2;
else if((c==ww && r<=hh)||(c<ww && r==hh)) cc.style.backgroundColor=c1;
}
}
}
}
</script>
<table border="1" id="tabella" cellspacing="0" cellpadding="3">
<tr><td>0,0</td><td>0,1</td><td>0,2</td><td>0,3</td><td>0,4</td></tr>
<tr><td>1,0</td><td>1,1</td><td>1,2</td><td>1,3</td><td>1,4</td></tr>
<tr><td>2,0</td><td>2,1</td><td>2,2</td><td>2,3</td><td>2,4</td></tr>
<tr><td>3,0</td><td>3,1</td><td>3,2</td><td>3,3</td><td>3,4</td></tr>
<tr><td>4,0</td><td>4,1</td><td>4,2</td><td>4,3</td><td>4,4</td></tr>
</table>
(4,3)
ciao ciao