Freecharge Interview Experience-Lead SDE


1) Design, develop and implement an elevator problem (only 20 minutes) Lots of discussion on why the approach is chosen. Advantages and trade-offs discussed.(For almost an hour)

1) All possible permutations of a string.
2) Design, develop and implement Phone directory. Implement a search algorithm on top of it that it does autocomplete Eg : %95% ( Result : 98769512345, 9545654312 etc having 95 sequence anywhere)
(Note : Not to use TRIE)
3) Design, develop and implement an OrderGenerating System in distributed servers.

1) No database should be used.
2) The orderID generated should be unique among all servers.
Lots of discussion on various approaches.
4) Difference between equals and hashcode in JAVA

Round3:(Hiring Manager Round)
1) Details about projects in CV.Explanation in detail
2) Check if Binary Tree is BST or not?