CareerCup

Find how many numbers of length n are there such that each number is at least 4 smaller/greater than the number before and after it.

Eg: if n = 5, such numbers are 39518, 15951, etc.

There are three closed doors. Behind two of them there are donkeys, behind the third one there is a Mercedes-Benz. (Your task is to get the Mercedes, not the donkey).
You are asked to choose one of the doors. Once you have chosen, they open one of the remaining two doors with the donkey. Now there are two doors left: one you chose and the other one. To maximize your chance of getting the Mercedes, should you keep your choice or switch to the other door?

write a program how many squares in chessboard ?

Implement hashtable put function in C++ without using STL stuff.

Given a matrix containing 0 and 1. Consider 1 as 'Land' and 0 as 'Water'. Find out the number of 'Islands' in the matrix. That is, set of all adjacent 1 will make up for an island.

For example:

[ 0 1 1 0 1 ]
[ 1 1 1 0 0 ]
[ 0 0 0 1 1 ]
[ 1 0 0 1 0 ]

This problem has 4 islands. ( consider set of 1s, vertically, horizontally and diagonally ).

Please provide Oracle SQL and PLSQL questions

Suppose you have strings read in from a stream, e.g., '()(,)(())'. Detect if the parenthesis pair up correctly.

Part 1: How would you use threads to solve the problem?

Part 2: He then gave me an iterative solution and asked how the problem can be done distributively across multiple components.

Given a hashmap, HashMap<String,List<String>> with the following data:

A: B,C
B: X Y
X: Z
Y: Z

Expected output is an array of the dependencies. I initially started with Breadh-first search for simplicy, which had running O(|V|+'E') and space O(|V|). The interviewer said depth-first search is better; I don't see how DFS is better, because it requires recursion.

Part2: He then said my solution is functionally correct and then introduced a circular dependency and asked how to resolve it. I said using a visited hashset will detect a circular dep. He said it's not quite right and there a few approaches.

Given a string of english characters. Find the character that appears only once. I used arr[256] to store a count of each character. Then, iterate over the array to find the first non-dup, a[iter+'a']==1. The interviewer thought that storing a[iter]='x' (dup) and a[iter]=<index> was a better solution to avoid running a second pass over the string. In my mind, I disagreed using the array index, one can find the character that appears only once. The interviewer persisted, and told me to think about it.

Write a function which takes a BST and then "flattens" it (converts in-place into new BST), so all the nodes have only right child and no left.
Example:

10
   /   \
  5   15

Output:

5
  \
  10
    \
    15

You are given an array representing integer. Write a function which increments this integer.
Example: input [1,2,3] (represents 123) -> output [1,2,4]

A single-elimination tournament with 64 teams. Before the tournament, fans construct fantasy brackets for their tournament predications. Design a data structure for storing fan brackets and algorithm to score their brackets against a winning bracket. Assume we will then need to quickly score a player’s predictions (1 point per successful round prediction) and your solution should be optimal enough to handle millions of fan brackets with minimal data.

Count triangles in an undirected graph where a triangle is a unique set of three vertices connected to one another.

Implement a bowling game. First person took 40 mins to make sure I understood the scoring of bowling. Got stuck on coding an open-frame/strike/open-frame and time ran out with the second interviewer.

class Frame
def initialize
@rolls=[]
end

def roll(pins_down)

end

def score

end
end


class Game
attr_reader :frames

def initialize
@frames=[]
end

def score

end
end

Write code in the language of your choice to determine how many numbers between 1 and 100,000 contain an even number of odd digits

What I understand that number of digit in a number should be odd
is..
2 4 6 8 are even number which having only 1 digit and 1 is odd number
10 12 14 18 ……are even number but number of digit in these number are 2. 2 is not odd number hence we gonna discard all these number

102 104 106 …. Are even number and number of digit in these number is 3 that is odd number hence we will count these number

1000 1002 1004….are even number and number of digit in these number is 4 that is even number hence we will not count these number…

Please let me know if you think differently.

Write an itoa

Not sure what topic this falls under.

"Improve metrics on the system."

Intentionally vague requirement to see how I ask questions. In my case, it ended up being a discussion about making database queries faster.

Given a string such as "123", convert it to an integer. Basically, write Integer.parseInt(string).

Given a CSV of names and ages, perhaps:

Alice, 30
Bob, 17
Clyde, 49

Sort the names by age.

Serialize & Deserialize a binary tree

Implemented a bounded queue:
Read:
If queue is empty, wait till it can return a value with time out
If another thread is reading from the queue then wait till that thread is done
Remove the first element from the queue and return it
Do not block if a thread is writing into the queue

Write:
If queue is full, wait till one value is read with time out
If another thread is writing to the queue, wait till that thread is done
Write the element at the end of the queue
Do not block if a thread is reading from the queue

Given a start string, end string and a set of strings, find if there exists a path between the start string and end string via the set of strings.
A path exists if we can get from start string to end string by changing (no addition/removal) only one character at a time. The restriction is that the new string generated after changing one character has to be in the set.
start: "cog"
end: "bad"
set: ["bag", "cag", "cat", "fag", "con", "rat", "sat", "fog"]
one of the paths: "cog" -> "fog" -> "fag" -> "bag" -> "bad"

Given an array of integers (+ve & -ve) find two equal sized contiguous non-overlapping sub-arrays with maximum dot-product

Write an OO class system for individual-contributors, managers, directors.

Minimize the cost to chop the log into pieces of desired lengths. The cost to cut any piece is the max of the two lengths generated out of cutting the wood. e.g. If a 14 unit log is cut into 2 pieces of lengths 6 and 8, cost is 8.
Write a function that takes the total length of the log and an array of piece lengths and returns the cheapest sequence to do this along with the cost

Given an existing inventory Oracle Database system and UI. The UI should update itself as soon as the db gets updated
There is a tool that people use to dump inventory data (one row at a time or bulk insert via data in files)
Currently a new system is built with new UI using No Sql database.
Write a bridge that will update the new UI and populate the No SQL database, so that the new UI has real time updates as the tool has updated.

What does the error "Null Pointer Assignment" mean and what causes this error ?
If found, what are basic approaches to debug this type of error ?

You have a very large array of integers. write this function

boolean hasTwoNumbersThatSumValue(int[] arr, int num)

1. A server can call an API once per second. How would you ensure that it calls 1/sec given that it's a multithreaded environment.

2. If there are multiple servers how would you ensure that the calls still remain 1/sec.

1. A server is getting streams of numbers from TCP IP. Write code to get minima/maxima for every 60sec. - The interviewer was looking for code with multithreading as you can perform print of minima/maxima for 60 sec interval and at same time do comparison.

2. If the stream can't be handled by one server and now there are multiple servers how would you calculate minima/maxima? To calculate what optimizations would you do.

3. If now you need to find 10 largest and 10 smallest elements how would you do?