Added junit dependency
Should return total of zero when there are no items
Should return total of 50 when A is scanned
Should return total of 30 when only B is scanned
Should fail unit test when scanning A+B
Should return total of 30 when only B is scanned
Refactored code when scanning A+B items.
Should fail test when scanning A+B+C+D items.
Should return 115 when scanning A+B+C+D items.
Refactored code.
Scanning items AA should return 100
Scanning items AAA should fail because discount is not applied
Scanning items AAA should return apply discount and return 120
Refactored code when applying discounts
Scanning items AAAA should return the total 180
Scanning items AAAAA should return the total 230
Should fail unit test when scanning 6xA items because discount is not being applied the second time.
Should apply two discounts when scanning 6xA and return total value of 260
Should fail unit test when scanning AAAB
Scanning AAAB should return the total of 160