static void Main() { Individual ivan = new Individual("Ivan"); Company tech = new Company("Tech OOD"); MortageAcount firstAcc = new MortageAcount(ivan, 1000, 3); MortageAcount mortAcc = new MortageAcount(tech, 20000, 10); Console.WriteLine(mortAcc.CalculateInterestAmount(10)); //10 months * 10% / 2 = 10months * 5% from 20 000 = 10 000 Console.WriteLine(mortAcc.CalculateInterestAmount(24)); //12m * 5% from 20000 and 12m * 10 % from 20000 = 12*1000 + 12*2000 = 36 000 Console.WriteLine(firstAcc.CalculateInterestAmount(7)); //only 1 month (first 6 are no rate) * 3% from 1000 = 30 DepositAcount depAcc = new DepositAcount(ivan, 700, 20); Console.WriteLine(depAcc.CalculateInterestAmount(99999)); // 0 - amount is 700 which is positive and less than 1000 LoanAcount loanIndivid = new LoanAcount(ivan, 10000, 10); LoanAcount loanCompany = new LoanAcount(tech, 100000, 15); Console.WriteLine(loanIndivid.CalculateInterestAmount(3)); // 0 - free 3 months Console.WriteLine(loanIndivid.CalculateInterestAmount(4)); // free 3 months --> 1 * 10% from 10000 = 1000 Console.WriteLine(loanCompany.CalculateInterestAmount(2)); // 0 - free 3 months Console.WriteLine(loanCompany.CalculateInterestAmount(4)); // free 2 months --> 2 * 15% from 100000 = 30000 }