This tag is for questions that came up in an interview.
1
vote
1answer
15 views
Is this loop-based Java code to reverse a linked list, efficient and self explanatory?
Triggered by an interview question (I didn't answer during the interview) I wrote a Java program to reverse a linked list. I went with a loop-based approach instead of recursion. I would like to know ...
3
votes
2answers
79 views
'Broken Record' Coding Challenge
I was asked to complete a coding challenge for an interview. The challenge being to write a test function to check whether or not a string was a broken record. A <...
6
votes
4answers
897 views
Implement an algorithm to determine if a string has all unique characters
I'm working through Cracking the Coding Interview. The first challenge is to implement an algorithm to determine if a string has all unique characters.
I've gone through several iterations, but here'...
1
vote
2answers
39 views
Pseudo Promise.all() polyfill
A few years back I interviewed with a company for a Javascript position. After a couple of warm-up challenges I was presented with this:
Please write a function that calls back with ...
5
votes
2answers
60 views
Java controller to farm out concurrent tasks
I've recently given a coding interview on a Java concurrency task and unfortunately didn't get the job. The worst part is I've given my best but now I'm not even sure where went wrong. Can anyone ...
4
votes
1answer
98 views
SVG photo mosaic creator
I got this as part of some interview assignment. After some head scratching I think I have done quite well as the result can be seen here:
After transformation(10x10 tile):
More crisp picture ...
5
votes
3answers
239 views
Finding the duplicate with an array with 1,000,000 integers between 1 and 1,000,000
I recently had an interview and got to phase 2 which is a coding assessment. One of the questions was:
Given an array with 1,000,000 integers between 1 and 1,000,000, one integer is in the array ...
12
votes
6answers
2k views
Find the first non-repeating character in a string: (“DEFD” → E)
I recently had an interview and got to phase 2 which is a coding assessment. One of the questions was:
Find the first non-repeating character in a string: ("DEFD" --> E)
I didn't pass the coding ...
1
vote
4answers
142 views
Program to display array elements in the ascending order of number of factors each element has
Input:
1000 23 100 26 32
Output:
23 26 32 100 1000
Since 23 has '2' factors and 26 has '4' factors and 32 has '6' ...
6
votes
3answers
217 views
Flatten an array
I have got this interview question which has asked me to write a production level code which flattens the arbitrary nested array of arrays.
Code
...
6
votes
5answers
269 views
A custom String Builder implementation
Two code files below : the actual logic & the test logic.
Core Logic
...
10
votes
3answers
2k views
Counting permutations without repetitions for a number or a string
Can I make the following code faster with minor modifications? It times out on CodeWars website.
...
2
votes
2answers
78 views
Returning a filtered list of iPhones
I have just received feedback regarding a junior dev test that I submitted. It was unfortunately not great, and the recruiter could not articulate the issues, I tried to show that I was thinking about ...
4
votes
1answer
65 views
Rails Sample for interview
I did a small sample application for an Interview. Since I didn't got accepted I would like your opinion on how to improve it.
The aux methods are private.
I have a ...
1
vote
0answers
42 views
Improving time efficiency of finding maximum area rectangles in a histogram
Here's my solution but I am looking for ways to improve the time complexity of solution. Also this question is categorized as being solved by stack so I would like to know how to approach it using ...
-4
votes
1answer
59 views
Recursive solution for merging two sorted lists [closed]
I came up with a recursive solution for merging two sorted list in Python in interviewbit:
Merge two sorted linked lists and return it as a new list.
The new list should be made by splicing ...
4
votes
1answer
106 views
Improving time complexity of finding the longest palindrome in Python
The Longest Palindromic Substring challenge from InterviewBit:
Given a string S, find the longest palindromic substring in S.
where a "substring" must be contiguous, and in case of ties the ...
3
votes
1answer
56 views
Create a generator that returns every permutation (unique arrangement) of positive integers up to n
I watched this video from The Unqualified Engineer on YouTube and tried out the challenge. The challenge (or interview question) is to build a generator that returns all the permutations of the ...
4
votes
3answers
930 views
Top 5 most common words in Python
I would like to hear feedbacks from an interviewer's perspective on how to improve the following code:
...
4
votes
3answers
155 views
Bitcoin trading system
Recently I did an exercise for a interview pre-screening, but was not selected. They did not give much detailed feedback apart from "the code was not up to what they wanted".
It would be really ...
14
votes
1answer
369 views
Match Three game for a job interview using Cocos2d-x
The problem is that I had an interview for a gaming company and I had to write a prototype of a Match Three style game. The time line was 3 days. I made the code in about 2 days and sent it to them.
...
3
votes
3answers
103 views
Find majority element in an array given constant external space
Given constant external space (yes no HashMap), how would you improve the following code (code-wise or complexity-wise with stress on the latter) to find the ...
1
vote
1answer
85 views
Rearrange String such that similar characters are placed at least 'K' distance apart
So I was asked this in an interview, and I had to write this code on a white board. Sadly I couldn't complete the code :( .
I've realized that writing code on white board is completely different ...
0
votes
3answers
102 views
Detecting if two given strings are isomorphic using Java data structures
So I have written the following code and it works for various same length isomorphic strings I have tried. However I am not sure what are some time complexity improvements and coding tweaks that could ...
2
votes
4answers
153 views
Reverse Polish Notation Evaluation in Java
I would like to hear feedback about my code both in term of improving efficiency if possible or using other data structures. Also go ahead and let me know about code styles/patterns.
...
6
votes
4answers
827 views
Detecting if two strings are anagrams using TreeMap
I decided to use Java TreeMap because it seems like a great data structure to fit this problem. However, I am not sure if there could be much simpler methods using ...
3
votes
1answer
62 views
Faster palindrome checker in Java
I wonder if there could be a faster palindrome checker in Java. The best one I have is O(n/2) which is O(n) eventually:
...
3
votes
2answers
69 views
Duplicates in array elements and sorting
I've been given this little test exercise for an interview as php developer, and I'd like to hear from you if my solution is good (enough) or if the problem could have been solved in a better way. ...
3
votes
2answers
60 views
Merge and sorting arrays of String and int in more efficient methods
Are there better methods for merge and sorting arrays of int and String in more efficient methods both time-complexity wise and ...
3
votes
2answers
132 views
C++ Graph Class Implementation (adjacency list)
I've got a barebones C++ graph class implemented as an adjacency list. The graph consists of a vector of vertices. Each vertex has a vector of outgoing edges that store the destination vertex id. ...
5
votes
1answer
114 views
Caches implementation in C++
I had a test task for internship where the main part was in implementing fixed size caches with different displacement policies (LRU/LFU/FIFO). I did that task, but was refused afterwards. Now I am ...
1
vote
0answers
33 views
Checking whether a directed graph contains a cycle
I create a myGraph class as shown below. Then I created an instance of the graph by giving the adjacency list as a NSDictionary and then call the isGraphCycleFree method. Will this answer look good ...
3
votes
1answer
56 views
Efficient File Searching
During an interview I was asked to consider the following:
You are trying to find an instance of an error code within a number of log files within a directory. The goal is to count the number of ...
4
votes
2answers
128 views
0
votes
3answers
59 views
Counting occupants in each HouseHold provided large file of comma seperated personnel records
I was given the below Exercise as part of a coding Exercise to do at home for a technical interview, and I did not get through past this round.
I would like to get some input on what i could have ...
4
votes
1answer
66 views
Sort a stack in descending order
Maintain current element as the top element in the input stack. Pop all the elements on the ordered stack which are greater than the current element and push them in to the input stack and maintain a ...
2
votes
1answer
48 views
Find the contiguous subarray within an array (containing at least one number) which has the largest sum
Interview Q: Find the contiguous subarray within an array (containing at least one number) which has the largest sum.
For example: Given the array [-2,1,-3,4,-1,2,1,-5,4], the contiguous subarray [...
5
votes
3answers
166 views
Interview coding test: Searcher
I did a task for an interview and the solution was not accepted. The task was to implement the class search function by name. The number of classes in the input data from 0 to 100000. Class names are ...
34
votes
7answers
12k views
Interview coding test: Fizz Buzz
I was recently given a coding test to complete for a potential client. It was a FizzBuzz-type of thing with a two-hour time limit. I had a request to write basic FizzBuzz, then add a special case, ...
-1
votes
1answer
58 views
Determining whether a string can be rearranged into a palindrome
For a string, count the number of occurences of each character. If at most one character has odd count then the string can be a palindrome else it's not.
...
4
votes
1answer
108 views
Finding number of times each string in an Array of strings occurs in a large stream of characters (i.e large string)
Interview problem:
Given a stream of characters (e.g. acacabcatghhellomvnsdb) and a list of words (e.g. ["aca","cat","hello","world"] ) find and display count of each and every word once the ...
1
vote
2answers
52 views
Calculate Kth Row of Pascal's Triangle
Purpose
Implement a solution that returns the values in the Nth row of Pascal's Triangle where N >= 0.
Math
First three rows ...
4
votes
3answers
216 views
Football game using factory and command patterns
I'm really confused about the interview I did with a firm. They told my code was not expert, but almost intermediate level java.
Requirements
Football Scoring Dashboard
Develop an application that ...
6
votes
3answers
435 views
Given an unordered list of numbers, find all pairs that add up to x
I am coding an interview question from Yahoo Software Engineer Intern Interview.
Given an unordered list of numbers, find all pairs that add up to x.
I have a working solution in Java:
...
2
votes
3answers
88 views
Minimum element in a sorted rotated array
A sorted array [0,1,2,3,4,5] when rotated n times (3 times in this case) becomes [3,4,5,0,1,2], meaning elements in the front move to the end. The code below finds the minimum element in this array, ...
15
votes
2answers
1k views
Python backend interview: task management system for workers
I've recently applied to a backend position and I was asked to complete a take-home interview question. I thought the question was rather simple and I completed in about an hour although I was told it ...
3
votes
2answers
127 views
Decimal number to binary number conversion in JavaScript
I made this decimal to binary conversion as an exercise for myself and because it is obviously often asked during job interviews / tests.
Any hints concerning possible improvements welcomed.
<...
2
votes
2answers
182 views
JavaScript function to convert decimal number to binary
I was recently asked this in an interview for a front-end position and I came up with something like this which seems to work but is clunky. (Number.toString() was ...
2
votes
2answers
39 views
Choose a color with probability proportionate to its weight in a group of colors
Input: An array of colors with weights. e.g [['red', 10], ['blue', 20], ['green', 30]]
Output: A random color from the array, based on it's proportion to the other ...
2
votes
3answers
137 views
Adding minutes to a time value in Ruby
I recently submitted a code-challenge for an interview according to the following guidelines:
About
Write a function or method that accepts two mandatory arguments and returns a result.
...
