You've pretty much got it, Magic_fubu. There are several ways to do it:
switch(r, 1, 19, 2, 17, 3, 15, 4, 13, 5, 11, 6, 9, 7, 7, 8, 5, 9, 3, 10, 1) + 1 + nh
This gives one less point than the ranks are supposed to get, but then adds 1 point (which everyone receives) so that those that aren't ranked in the top 10 get the 1 point. + nh gives one point for each hit a player makes (each knockout), which is what I assume "Hit man = 1" means.
The other way to do it is very similar:
switch(r, 1, 20, 2, 18, 3, 16, 4, 14, 5, 12, 6, 10, 7, 8, 8, 6, 9, 4, 10, 2, 1) + nh
This is the same except we give the proper points in the switch(), and add a final parameter to it: ", 1". That's the "else" clause, which says if they don't match anything in the switch, then return this value. So, for those that aren't in the top 10, they get 1 point from the switch statement.
And another way:
if(r < 11, (11 - r) * 2, 1) + nh