CareerCup

Design a system to forward 20% of your requests to cloud datacenter and rest to onprem data center. comsider you are fwd api.

Design S3 file storage system.

Last Man Standing
A king gathers all the men in the kingdom who are to be put to death for their crimes, but because of his mercy, he will pardon one. He gathers the men into a circle and gives the sword to one man. The man kills the man to his left, and gives the sword to the man to the dead man's left. The last man alive is pardoned.

With 5 men, the 3rd is the last man alive.

Write a program that accepts a single parameter: a number N that represents the number of criminals to start with. The program should output the number of the last two men alive.

Example #1: myProgram 5

would output:

5, 3

Example #2: myProgram 7

would output:

3, 7

This is a word splitter program, I wanted to know the complexity of this program:

String s = //"The quick fox jumped over a lazy dog";
           "The Java language provides special support for the string " +
           "concatenation operator ( + ), and for conversion of other " +
           "objects to strings. String concatenation is implemented " +
           "through the StringBuilder(or StringBuffer) class and its " +
           "append method. String conversions are implemented through " +
           "the method toString, defined by Object and inherited by " +
           "all classes in Java.";
int charLimit = 13;
System.out.println("-------------");
char[] chars = s.toCharArray();
boolean endOfString = false;
int start = 0;
int end = start;
while(start < chars.length-1) {
    int charCount = 0;
    int lastSpace = 0;
    while(charCount < charLimit) {
        if(chars[charCount+start] == ' ') {
            lastSpace = charCount;
        }
        charCount++;
        if(charCount+start == s.length()) {
            endOfString = true;
            break;
        }
    } 
    end = endOfString ? s.length()
                      : (lastSpace > 0) ? lastSpace+start : charCount+start;
    System.out.println(s.substring(start, end));
    start = end+1;
}

Aisles contain products. Product is only going to be in one Aisle.

Product{

AisleID: string

ProductID: string

Price: float

}

Given Array<Product>, find the N highest price combinations. Combination is 1 product from each aisle. You can choose only one instance of each product.

So if you had two aisles

1: {$5,$4,$2}

and

2: {$6,$1)

And they asked for the 2 highest combos you would give $6,$5 and $6,$4

Fill the arrow with zeros in n*n matrix.{{0,0,0,0,0,0,0
0,0,1,1,1,0,0
0,0,1,0,1,0,0
0,0,1,0,1,0,0
0,1,0,0,0,1,0
0,0,1,0,1,0,0
0,0,0,1,0,0,0}}

Given a math expression in string format that contains only + & - and numbers. Return the sum in integer format. Eg: Input: "3+4-7+13" Output: 13.
"2+1-8+13" Output: 8

Print words in order which are occurring once in huge document. The RAM size 100MB and file size 10 GB.
Example: I am good. You are good.
Answer : I am You are
Note : It's not datastructure problem where we can simply make use of LinkedHashMap. The file size is going to be huge.

I participated interview event with Amazon and receive email from Amazon recruiter that the team was happy with my performance and would be giving me offer at Amazon Vancouver Office, Canada. However,17 days later i still not get an official offer. I did several follow up with the recruiter within the period, just to get some "they are finding team for me" response. What could go wrong? Why is it in my case that the offer is being process so slow?

given two array of elements representing the connection Nodes output the topology used?
Topology can be either Bus , circular or Star

input:
Number of nodes 3
Number of Connections : 2
{1,2}
{2,3}

Output Bus
Explanation
the topology formed would be 1->2->3 . hence Bus

input
number of nodes : 3
Number of connections : 3
{1,2,3}
{2,3,1}

Output: Circular
the topology formed is 1->2->3->1
hence circular

input:
number of nodes : 5
Number of connections : 5
2 3 4 5
1 1 1 1

Answer : StarTopology
Explanation : A star can be formed with this input
2 4
1
3 5

StarTopology

Design a system which helps to calculate average Skype call duration per day. In which events are tracked from mobile app. Need to take care of all edge cases like events can be logged to server in any sequence & there can be some events missing on server side also.

A message containing letters from A-Z is being encoded to numbers using the following mapping:

'A' -> 1
'B' -> 2
...
'Z' -> 26
Given an encoded message containing digits, determine the total number of ways to decode it.

For example,
Given encoded message "12", it could be decoded as "AB" (1 2) or "L" (12).

Design online multiplayer generic board game (like chess). How will you store sessions.(RDBMS or REDIS) How will the
competitor be chosen and notified(HTTP or what?).
What are the appropriate classes?

Design Recommendation system. How will you generate generate recommendations for millions of users. DB Schema, How will you improve latency? if the user is searching a item, when will you show next recommendations. How will you update, latency basically and consistency.

You are provided with 2D char array. You have to provide the 2D char array as response which contains the multiplication od the input array. For eg: input=> {{a,b},{c,d}}, output => {{a,c},{a,d},{b,c},{b,d}}

You are provided with different Excel files and the data format those files contain. You are also provided with low level parser. You have to design a system which takes the excel file and its data type as the input and returns the list of Data objects in the file.

Design JProfiler. How will you design datastructure and why, function stacktrace. HLD+LLD

Design a Fresh Grocery System. Means Daily usable Items, you cannot store them in inventory like bread, milk etc.
HLD+ DB Schema + Concurrency issues + Scalable architecture. How will you scale to multiple countries

How to develop a web based multiplayer chess game. There will be 2 player in each session. There will be multiple sessions.

My answer(I was not selected)
Each player will have a database with columns
user id(primary key), passwd,no of games played, won,drawn,last active time,sq1,sq2,...sq64,move made flag,pawn num, sqstart,sqend
where sq1-denotes square 1 and its value represents the pawn num in sq1
question- what all fields in database will be encrypted
answer-passwd
question- why not others
answer-may be system admin needs to access them
question – how will u start a session between players?
Answer-When a player logs in, his last active time is updated. Each player is shown a list of last active players to chose from.Or system can arbitrarily select one.When a player is selected, he gets a request. Each player receives a list of requests from other players. He choses from one. That player gets an acknowledgement others get negative acknowledgement. If acknowledgement does not come in time then that player is dropped and another player is selected.
Question- http connection, can not send request from server. How the 2 players will send request to each other and how session will be initiated?
Question-how the game will be stored?
The 64 squares sq1,sq2,..sq64 will each store the pawn number in them. From random number calculatio, it will be decided which one is white and which one is black 1st time. When a player makes move,has made move flag will be true. The last move is stored as sqstart,sqend,pawn number. Each time a move is made check for valid move.The other player continuously polls for has made move flag to know if it is his turn
remarks- ur design is not scalable.

You are given a Log that contains UserId, ProcessId, Start Time, End Time and Resource Consumption during that time, you need to find out the user who has utilized the most resources.

Example:

UID    PID    StartTime    EndTime     Consumption

1        1        200       300             100

2        2        230       340             80

1        3        245       315             50

1        4        305       330             20

Time 200 signifies: 02:00.


Output: UID# 1
UserID 1 because he has consumed the most number of resources between 200 to 315 (Resource Consumption: 150).

Design an order tracking system using the below constraints.

Once an order is received, it will be assigned to a delivery boy and sends notification at every stage of the order such as order received with expected time of delivery, delivery boy assigned, order picked up, order delivered.

State how your design will help scale and what will be the performance SLAs that will you will set for your design. The system should be able to horizontally scalable from hundreds of orders to million orders and should perform at almost the same level irrespective of the number of orders received.

Singleton Design pattern. How you make it double ton(in even call of getInstance() first object should be return and odd call of getInstance() second instance should be return). Make it triple ton.

Print series 010203040506. Using multi-threading 1st thread will print only 0 2nd thread will print only even numbers and 3rd thread print only odd numbers.

Add a digit to a number that is represented by a linked list, where each node is a digit of the number. The linked list couldn’t be modified, except the digits to be modified in answer and the number could be infinitely long. Need to do it in O(1) space.

Find the Minimum length Unsorted Subarray, sorting which makes the complete array sorted

Maximum difference between node and its ancestor in Binary Tree in O(n) time.

Given a very large binary number which cannot be stored in a variable, determine the remainder of the decimal equivalent of the binary number when divided by 3. Then generalize to remainder of any number 'k'

Given a pre-order traversal, construct a binary search tree in O(n) time.

Given a large text file, find an efficient algorithm to find the least distance(measured in number of words) between any two given words.

Given a set of start date and end date design a data structure to return a given date falls in.

Example
1Sep 2016 - 10 Sep 2016
1 Jan 2009 - 31 Aug 2015

given 12 Jan 2014 should return 1 Jan 2009 - 31 Aug 2015