Create a code to control finances using unity3d

Hi, guys I need help to programing code. The software supposed to work like that: Control finances, and show what each person spent and what each person supposed to receive from one purchase. beers, beef, coke and rental are enum, will appear a check box for user choose what kind of category he spend the money. Example: A - bought 20US in beers B - bought 60US in beef C - bought 10US in Coke D - rent place for 100US ---------------------------------- With another check box, the user who bought something can chose who will share that bill. Example A - beers -> split with A,B B - beef -> split with A,B,C C - Coke -> split with B,C D - rental -> split with A,B,C,D ---------------------------------- The system supposed to return how much each one have to pay and receive from each one. A -> Have to Pay 10US to B Have to Pay 25US to D B-> Have to Pay 25US to D Have to Receive 10US from A Have to Receive 15US from C C-> Have to Pay 15US to B Have to Pay 25US to D D-> Have to Receive 25US from A,B,C ----------------------------------