Labeling foreground and background branches for positive selection anaylysis

[JAM]

Hi everyone,

           I want to learn to how to test for positive selection in specific branches on a tree using, the branch site model. I'm having trouble understanding how to label the branches on the tree, for example I made a practice tree and I want to test if positive election has occurred on branches 2,3, and 4. Where would I place "#1" on the tree?  I think they placement of "#1" on B is correct, if wanted to test for selection on branches 2,3, and 4 or am I wrong? I have attached a screen shot for you to see the tree, the branches in blue are the ones I want test for positive selection (foreground) and the black branches are the background.

My practice tree =(1,(2,(3,4)),5)

Labeled tree

A- (1 #1,(2,(3,4)),5#1)

B- (1 ,(2,(3,4)#1),5)

C- (1 #1,(2,(3,4)),5)

[Sishuo Wang]

I think it is something like (1 ,(2#1,(3#1,4#1)#1)#1,5)