vbs Inputbox - how to set focus at the end of a default value

Hi,

In a vbs script
1/ how to set the focus at the end (sendkeys end??) of the default.
In this example
I wish the focus to be after "2"

2/ how to set the focus at the last before end character, in the preceding example it would be "-"

Thanks

P.S. I tried InputBox ("Give a pair of numbers", "title", "1-2" & Chr(3) ), but doesn't work.