Birthday Calendar

Implement the birthday diary calendar to keep records of all birthdays of your friends
1) what underlying data structure(s) you will use so that the memory consumption should be optimum [i.e if you have only 12 birthday entries you should not hold memory for all 365 days of the year].

2) You should be able to view the data (birthdays) with closest birthday first [i.e 7th July should come before 11 Aug].

3) How will you keep this data sorted (for question 2), everytime you insert a new birthday entry. This sorting should be as optimum as possible [mergesort etc will not be very beneficial bcoz ideally you won't have thousands or millions of birthday]

4) How will you handle 2 or N number of birthdays on same day