I have a scoring spreadsheet for tracking a golf competition. In it, players
have a handicap (1-28) and each hole has a stroke index (1-18) which
signifies how easy each hole is (1 hard, 18 easy).

I am trying to work out a formula that assigns the right number of shots
each player based on the handicap and stroke index.

For example, if I have a handicap of 21, I will get 1 shot on all 18 holes,
and extra shot on the three hardest holes (those with SI of 1 to 3).

So the formula is to return a value of 0, 1 or 2.

Can anyone help? Thanks in advance!

Nigel