Amazon Interview Report
- 0of 0 votes
AnswersSuppose a customer buys items for $10 in a shop and the cashier swipe her card at a POS charging $10. Assume that the card has $100 balance before swiping. POS sends the $10 transaction to a machine A in the Amazon cloud. A calls a service to update transaction and card balance, and then sends acknowledgement back to the POS. But the ack got lost in the middle and POS sends another $10 transaction request. How would you make sure that the balance is $90, not $80. And how would you distinguish multiple try with two legitimate $10 transaction back to back.
- zahidbuet106 February 13, 2013 in United States
Hint: You can't use more than one transaction entry in Database and you don't have the rollback provision.| Report Duplicate | Flag | PURGE
Amazon Software Engineer / Developer Database - 0of 0 votes
AnswersGiven a BST and a node, write the BST data structure and a method in Java
- zahidbuet106 February 13, 2013 in United States
Node findNode(Node n)
that will find the next node of n in the BST. For example, if the tree looks like:
7
/ \
5 11
/ \ /
4 6 9
/ \
2 15
Then,
findNode(2) = 4,
findNode(4) = 5,
findNode(5) = 6
findNode(6)=7
findNode(7)=9
findNode(9)=11
findNode(11)=15
Note that you are not given the root of the tree.
Hint: you may assume that you have parent pointer.| Report Duplicate | Flag | PURGE
Amazon Software Engineer / Developer Algorithm - 1of 1 vote
AnswersSuppose we are detecting fraud cheques and we found the cheques with the following list of patterns are fraud:
- zahidbuet106 February 13, 2013 in United States
111122234455
1234
22334455
11111111
234567
etc.
Now if you have a new cheque and wan to detect fraud in O(1) time what data structure you want to use?| Report Duplicate | Flag | PURGE
Amazon Software Engineer / Developer Data Structures