How to move throught pad from canvas

ROOT
1

Hello,
I would like to create a canvas of this shape

/------------------\
|..........|.......|
|.....1....|...2...|
|----------|.......|
|.....3....|.......|
\------------------/

It is like the seconf pictures of this page: root.cern.ch/root/html/TPad.html but in another direction.
What are the command what I need to type and what do I need to type to move to Pad 1, 2 and 3?
Thanks

2 
{
   TCanvas *c1 = new TCanvas("c1", "c1",15,48,700,530);

   TPad *c1_1 = new TPad("c1_1", "newpad",0.05,0.06,0.5,0.9);
   c1_1->Draw();

   c1_2 = new TPad("c1_2", "c1_2",0.5,0.5,0.9,0.9);
   c1_2->Draw();

   c1_3 = new TPad("c1_3", "c1_3",0.5,0.06,0.9,0.5);
   c1_3->Draw();
}