CareerCup

Use synchronized, wait() and notify() to write a program such that below mentioned conditions are fulfilled while reading and writing data to a shared resource.

When a write is happening, no read or other write should be allowed(read and write threads should wait)

When a read is happening, no write should be allowed (write threads should wait) but. other read threads should be able to read.

Donot use any API classes e.g. ReadWriteLock, AtomicInteger etc..

Design election voting system. Election would be country wide. System should be scalable, available and consistent.

Given three integers x,y and z you need to find the sum of all the numbers formed by 
having 4 atmost x times , having 5 atmost y times and having 6 atmost z times as a digit.

input 
x=1,y=1,z=1
output
4+5+6+45+54+56+65+46+64+456+465+546+564+645+654=3675

Given three integers x,y and z you need to find the all the possible combination of numbers having 4 at most x times, having 5 at most y times and having 6 at most z times as a digit.

input x=1,y=1,z=1
output

4
5
6
45
54
56
65
46
64
456
465
546
564
645
654

A Doctor travels from a division to other division where divisions are connected like a graph(directed graph) and the edge weights are the probabilities of the doctor going from that division to other connected division but the doctor stays 10mins at each division now there will be given time and had to find the division in which he will be staying by that time and is determined by finding division which has high probability. Input is number of test cases followed by the number of nodes, edges, time after which we need to find the division in which he will be there, the edges starting point, end point, probability. Note: If he reaches a point where there are no further nodes then he leaves the lab after 10 mins and the traveling time is not considered and during that 10min at 10th min he will be in next division, so be careful

find the division with highest probability that doctor is in it after 10 min is div 3 and probability is 0.7.

After 9 minutes dr has yet to move to another division he is in div 1 and probability is 1.0. Forty minutes later the division with highest probabilty is 6 and probabilty is 0.77400

input 1 6 10 40 1 2 0.3 1 3 0.7 3 3 0.2 3 4 0.8 2 4 1 4 5 0.9 4 4 0.1 5 6 1.0 6 3 0.5 6 6 0.5

output 1 6 0.774000

input 2 6 10 10 1 2 0.3 1 3 0.7 3 3 0.2 3 4 0.8 2 4 1 4 5 0.9 4 4 0.1 5 6 1.0 6 3 0.5 6 6 0.5

output 2 3 0.700000

Implement following method of ScheduledExecutorService interface in Java

schedule(Runnable command, long delay, TimeUnit unit)
Creates and executes a one-shot action that becomes enabled after the given delay.

scheduleAtFixedRate(Runnable command, long initialDelay, long period, TimeUnit unit)
Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given period; that is executions will commence after initialDelay then initialDelay+period, then initialDelay + 2 * period, and so on.

scheduleWithFixedDelay(Runnable command, long initialDelay, long delay, TimeUnit unit)
Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given delay between the termination of one execution and the commencement of the next.

Implement BST Iterator and use them in 2 sum and 3 sums problem on a BST

Implement a rate limiter that multiple threads can use, while the global rate is limited to a value

Implement a thread-safe data structure which can keep track of number of incoming
requests grouped by IP Address over a time window. Add support for grouping by other
attributes such as BrowserAgent.

Given an array sort even element 
and odd number and such 
that even element at even index and
 odd at odd and you have 
to return minimum no of swap 
and it has should be sorted 
input 2134
output 1

Given a string select two non-overlapping strings that are same and remove them. Perform this operation recursively till there are no desired strings.
Print the number of possible substring after completing above operation.
Ex - abcc
Duplicate non-overlapping substring - abc
After removing abc from we are left with 1 substring abc.

In a 2-D matrix of m*n select m-1 elements from each row such that that the resulting sum is minimum and each column is selected atleast once.

Ex -
2 3 5
3 2 5
4 4 7
Selecting (2,3) from 1st row, (2,5) from 2nd row and (4,4) from 3rd row would result in minimum sum of 20

Question: Can you break the given string into words, provided by a given hashmap of frequency of word as <word: n>

Example:
HashMap -> {"abc":3, "ab":2, "abca":1}
String: abcabcabcabca
output: Yes; [ abc, abc, abc , abca ]

Example:
HashMap -> {"abc":3, "ab":2}
String: abcabab
output: No

Example:
HashMap -> {"abc":3, "ab":2, "abca":1}
String: abcx
output: No

Find LCA for list of nodes of a tree

Function defined as below -
TreeNode findLCA(TreeNode root, List<TreeNode> nodes)

Given a number n, make a set of m integers such that the integers lie between [1, n] 
and the sum of  two integers should produce an integer which is in the set.

Eg. **Input**
n=20, m=5
**Output**
[3, 6, 11, 14, 17]

Which test types we can use for drinks vending machine testing? Especially for check dimension, length, appearance of machine and cups?

A set of points in the 2D plane. Find the first k number of points with the shortest distance to the point (0, 0), where k is a positive integer.

e.g.
Input
{[-16, 5], [-1, 2], [4, 3], [10, -2], [0, 3], [-5, -9]}
k = 3

Output:
{[-1, 2], [0, 3], [4, 3]}
.

A matrix represents a sequence of travel points. One only can travel either left/right or up/down. Some of those points are dead points which one can't travel any further. There is a destination point in the matrix. Find the shortest path from the top left point (1, 1) to the destination.

e.g.
Input
[
[‘O’, ‘O’, ‘O’, ‘O’],
[‘D’, ‘O’, ‘D’, ‘O’],
[‘O’, ‘O’, ‘O’, ‘O’],
[‘X’, ‘D’, ‘D’, ‘O’],
]

Output
Route is (0, 0), (0, 1), (1, 1), (2, 1), (2, 0), (3, 0) The minimum route takes 5 steps.

I was asked to integrate linkedIn and dropbox. So linkedIn is not into file storage system, hence they want to use the services of dropbox. The goal is to create, update, delete the documents of a profile in linkedIn. But these documents will not be stored in linkedIn. They will be stored in dropbox.
Moreover, to get this integration, linkedIn does not want to scale up they system. This means, if they have 400 servers, they do not want to add any more servers to achieve the integration.
How can I design this?

Given a positive integer array and a positive integer. Find a pair of integers in the array so that the sum of the pair is the largest one among all pairs not larger than the given integer.

e.g.
Input
{90, 85, 75, 60, 120, 150, 125}
d: 250

Output:
{90, 125}

Design DB schema for maintaining e-commerce various category ,sub category ,sub-sub category and so on.

Write a program to find number of words in a file not using any standard tokenizing API's.

Given n, you will be getting stream of sets each set may contain like (1,3,4,5) which signifies that 1,3,4,5 are related. Similarly you may get like (6,7) , (1,8).
And you will be asked to find whether 1 & 4 are related => Yes (as they are from same set).
3 & 8 are related => yes as 8 & 3 are related through 1.
5 & 7 are related =>No

Card Game

Card game rule: the hand is drawn from a pack of cards (no jokers).
Play cards ONLY when they are
1. 3 of a kind ('AAA' ) or 4 of a kind('AAAA’).
2. a straight flush of 3 or more cards('JQK' or 'A23456...' in the same suit).
Find out whether the player is able to play the whole hand given.
e.g. [Spade A, Spade K, Spade Q, Diamond Q, Heart Q] return false.
[Spade A, Spade K, Spade Q, Diamond Q, Heart Q, Club Q] return true.

Shopping Cart Programming test.
There are multiple types of customer(Regular, Premium) they have been given a discount based on their purchase amount. for e.x
Premium Customer
1) 0-$5000 0%
2) $5000-$10000 10%
3) 10000 - above 20%

Regular Customer
1) 0-$4000 10%
2) $4000 - $8000 15%
3) $8000 - $12000 20%
4) $12000 - above 25%

Read input from console:
Input:
Regular
$5000
Output:
$5000
Input:
Premium
$7000
Output
$8000

Implement a function which accepts a number and returns top 10 big numbers the function is called with so far;

If we call the function with 1.. to 100 , for the call function(100) the function will return 91 to 100 in reverse order since they are top 10 biggest number so far

Implement a fair mutex

An array is called a Good Array if the elements continually increasing or continually decreasing or continually decrease and then increase.
Question 1: He asked how will you tell whether a given array is a good array or not.
Question 2: Given an array, you are allowed to add any number of values to each of the element. Find the minimum sum of elements that can make the array a good array.

A software-based LRU Cache replacement algorithm has to be implemented for a Single Touch/Multi-Touch Cache. Single Touch can occupy at least 30% of the total cache space. A key accessed for the first time will appear in the Single Touch cache. When accessed multiple times, this will be part of the multi-touch cache. Also, multiple threads will access the cache. Following are the functions allowed for cache access.
1. get(key): returns the value against the key if present else return NULL
2. set(key, value): set the value against the key

Given a tree, and there will be treasure in one of the nodes. We can query any node, it will return the node itself if it contains the treasure or it returns the branch which leads to the treasure. we need to find out the treasure in minimum number of queries.