Help with Stock Merger Formula in Corp Finance

I am writing down formulas most every day, but find that I lack an easy way to remember how to calculate the gains to acquirer and target in a stock purchase. You have to account for new shares diluting old shares, etc. There isn’t an easy way presented to us in either CFAI or Schweser. Anyone have this written down so I can just memorize it? I’m fair certain there is a decent chance this will be asked. Thanks.