Thought work Coding Round 2011

Thought work Coding Round 2011
 They gave us a program of ipod inventory..the question was..
There is a company which have started selling the ipods ONLINE . But they want to sell these ipods online at best price.
i) They have ipod Inventories at Brazil and Argentina. Each of the inventory can store only 100 ipods.
ii) ipods at Brazil are sold at 100$/unit  and at Argentina they are sold at 50$/unit.
iii) after every order the stock at both brazil and argentina inventories are again back to 100 units.
iv) the no of ipods ordered should be only in multiple of 10.(i.e no of ipods ordered shouldnt be im number like 123 etc. )
v) the order placed should be either fullfilled completely or nothing
vi) if the order is placed like 120 ipods from brazil then the remaining ipods can be brought from the other inventory i.e.argentina.
     but here shipping price of 400$ per 10 units is applied.
they have also given the 4 set of inputs and outputs which your program should produce
:
: :
i) Brazil : 5
    500 : 95 : 100
ii) Brazil : 50
    4500 : 100 : 50
(this trick here is u first have to calculate the cost prize at both brazil and argentina..and d one which is low should be given..here argentina)
iii) Argentina : 120
     7800 : 80 :20
(this was the case where i made a silly mistake...out of 120 only 100 ipods should be sold according to the price at argentina..while reamaining 20 should be sold at prize at brazil which is 100$ + shipping charges (800$))
iv) Argentina : 250
     Out of stock!!!!
this program seems simple..bt the apparoach is important...my friend caluculated it according to country while i first checked the prize and based on that selected a country..
here they will check your code..see the logic. will ask some qstns..and they can also ask to change smthng in your code like prize or amount...they are just checking how logically strong you  are..try and avoid using switch or if else loops..keep it simple and short...