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Questions tagged [interview-questions]

This tag is for questions that came up in an interview.

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2
votes
1answer
1k views

Print concentric rectangular patterns

I am solving interview questions from here. Problem : Print concentric rectangular pattern in a 2d matrix. The outermost rectangle is formed by A, then the next outermost is formed by A-1 and so on....
6
votes
3answers
1k views

Reverse Polish Notation calculator with unit tests

I had an interview with a global company yesterday. They had given me a programming assignment. I shared my screen and I must have finished the task in 1.5 hours. Task was programming Reverse Polish ...
0
votes
3answers
458 views

Calculate median of a matrix

I am solving interview questions from here. Problem : Given a N cross M matrix in which each row is sorted, find the overall median of the matrix. Assume N*M is odd. Note: No extra memory is ...
4
votes
2answers
323 views

Consume etherscan.io API, store in DB, serve from web app

I didn't make it to the next stage in this interview process, because another applicant did better than me, which wasn't surprising given that this was my first foray into Node.js. I'd like some tips ...
2
votes
0answers
607 views

Robot on a Grid: Find a path between two corners with forbidden cells on the road

Problem statement The problem is defined in the book as following: 8.2 Robot in a Grid Imagine a robot sitting on the upper left corner of grid with r rows and <...
13
votes
3answers
13k views

Get all combinations of selecting k elements from an n-sized array

Was asked this today in an interview. Didn't see it before, and spent quite a lot of time getting it to work (tricky with all the recursion). The goal was to find all possible combinations of ...
6
votes
2answers
3k views

Find maximum gap between elements of an array

I am solving interview questions from here. Problem : Given an array A of integers, find the maximum of j - i subjected to the constraint of A[i] <= A[j]. Example : A = [3 5 4 2] Output :...
4
votes
1answer
764 views

Find currency exchange rates

Description: Design a service to fetch exchange rate from a remote resource and then calculate the exchange rate for each currency pair. The remote resource contains the exchange rates of ...
3
votes
4answers
155 views

Find the longest length of sequence of 1-bits achievable by flipping a single bit from 0 to 1 in a number

Problem Statement The problem is defined in the book as following: 5.3 You have an integer and you can flip exactly one bit from 0 to ...
6
votes
2answers
186 views

Convert csv to switch commands Python

The script should be a single python file that takes an excel file (or csv). Each row represents one switch. For each switch, there will be one or more interfaces. The objective is to output a ...
3
votes
3answers
650 views

Weighted Probability in Go

I was recently tasked a programming assignment with a prospective company, unfortunately I didn't pass the assignment and didn't receive any feedback on what I could have done better. I would ...
0
votes
2answers
392 views

Number of Paths (BackTracking) in Java

Illustration You're testing a new driverless car that is located at the Southwest (bottom-left) corner of an n×n grid. The car is supposed to get to the opposite, Northeast (top-right), corner ...
3
votes
5answers
930 views

Award Budget Cuts implementation in Java

PRAMP Award Budget Cuts The awards committee of your alma mater (i.e. your college/university) asked for your assistance with a budget allocation problem they’re facing. Originally, the committee ...
6
votes
1answer
187 views

Multiple stacks implemented via a linked lists on top of single fixed-size array

Problem Statement Originally, the problem is defined in the book as following: Describe how you could use a single array to implement three stacks. — Cracking the Coding Interview (6th edition) ...
2
votes
2answers
2k views

Program to shorten URL and decode it back to get original URL

TinyURL is a URL shortening service where you enter a URL such as https://leetcode.com/problems/design-tinyurl and it returns a short URL. Design the encode and ...
6
votes
2answers
755 views

Counting ambiguous Morse Code encodings, with and without Java Streams

Unique Morse Code Words International Morse Code defines a standard encoding where each letter is mapped to a series of dots and dashes, as follows: "a" maps to ...
0
votes
2answers
390 views

Pancake sort inteview using java

Given an array of integers arr: Write a function flip(arr, k) that reverses the order of the first k elements in the array <...
14
votes
3answers
1k views

Equation Evaluator

I am currently applying to many Software Engineer positions, and have been asked to complete several coding challenges. The most recent was an equation evaluator, written in C++, that was supposed to ...
4
votes
1answer
60 views

Code improvements for React App

This was my code challenge for a Junior JavaScript Developer position. The app is mostly running error-free, but I was rejected for the role, so I assume there were major issues with my code and have ...
2
votes
1answer
92 views

Let us schedule a meeting

Description: Write a method mergeMeetings() that takes a list of multiple meeting time ranges and returns a list of condensed ranges. The integers represent the number of 30-minute blocks past 9:...
-4
votes
1answer
510 views

Jumps of a pawn - Java interview [closed]

I have just attended a code test of some code testing site, and I think one question seems easy but I didn't get a high correctness, so if anyone can review this code snippet, I would appreciate it. ...
2
votes
1answer
652 views

Array partition 1 to group the array into pairs and make sum of minimum of pairs as maximum

Challenge from LeetCode: Array Partition I Given an array of 2n integers, your task is to group these integers into n pairs of integer, say (a1, b1), (a2, b2), ..., (an, bn) which makes sum of min(...
17
votes
2answers
3k views

Pancake sort interview with Python

I got asked this question during my interview. You can find information about this question here. Pancake Sort Given an array of integers arr: Write a function flip(arr, k) that reverses ...
3
votes
1answer
158 views

Find The Duplicates using binarySearch python

I got this interview question from Pramp. You can find it online through their website: https://www.pramp.com/challenge/15oxrQx6LjtQj9JK9XlA Find The Duplicates Given two sorted arrays ...
2
votes
2answers
4k views

Find the minimum number of coin change

Description: You are given coins of different denominations and a total amount of money amount. Write a function to compute the fewest number of coins that you need to make up that amount. If that ...
-1
votes
1answer
76 views

How to use C to solve Two Sum correctly? [closed]

Two Sum Problem: Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solution, and you may ...
4
votes
1answer
70 views

OOP air conditioner model

I had a phone interview and we shared a screen to do a simple challenge. Instructions were ambiguous but I basically had to implement how an air conditioner would work in general. I wrote the ...
2
votes
3answers
691 views

C++ interview problem: finding an Island in a 2D grid

I was asked this question from an online coding interview and I have provided my solution that passes all of the test cases. I wanted to see if someone can review my code. You can find my solution ...
6
votes
1answer
152 views

Searching the Array Index & Element Equality

I was asked this question from online coding interview and I have provided my solution that passes all of the test cases. I wanted to see if someone can review my code. Array Index & Element ...
5
votes
1answer
696 views

Roman to Arabic numerals converter in Javascript

I was given some homework as a technical test by a company I wanted to work for... Which I failed to the point of not being able to even access the code review portion of the interviewing process. ...
4
votes
1answer
833 views

Rate calculation system for a code challenge

This code challenge was part of a interview process I had applied for, and from which I was discarded after this test. I'd like to hear what other people have to say, hopefully in deeper detail. The ...
2
votes
2answers
1k views

Swap Nodes in Pairs in singly linked list

Description: Given a linked list, swap every two adjacent nodes and return its head. For example, Given 1->2->3->4, you should return the list as 2->1->4->3. Your algorithm should use only ...
3
votes
3answers
438 views

Merge intervals

Given a collection of intervals, merge all overlapping intervals. For example, Given [1,3],[2,6],[8,10],[15,18], return [1,6],[8,10],[15,18]. GitHub ...
0
votes
3answers
463 views

Remove nth node from last position in linked list

Description: Given a linked list, remove the nth node from the end of list and return its head. Given linked list: 1->2->3->4->5, and n = 2. After removing the second node from the end, the ...
1
vote
1answer
154 views

Maximum product of a triplet in array in linear time

Given an array of integers, find the highest product you can get from three of the integers. Input: [1, -4, 3, -6, 7, 0] Output: 168 I would love to hear from how this might be refactored/...
2
votes
1answer
99 views

Find the third largest element in the array in linear time

Find Third largest element in an array Input : arr[] = {1, 14, 2, 16, 10, 20} Output : 14 Its a simple program, but would be great to know how it can be improved for better readability or ...
6
votes
3answers
332 views

Intersection of the interval set

Recently I had an interview where it was asked: Given a list of people with their birth and end years find the year with the most number of people alive. I implemented in Java and was trying to ...
5
votes
2answers
703 views

Merge non overlapping intervals

Merge Intervals Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary). You may assume that the intervals were initially sorted according to their ...
3
votes
1answer
6k views

Filter out non-alphabetic characters from a list of words

For coding practice / interview exercises, I'd like to know if there's an optimizaton I can make to the following, where I "clean" a given word to remove punctuation or other characters that are not ...
8
votes
2answers
768 views

Sequential execution

I made a class that I think satisfies the conditions: Actions can be added to the queue at any time by any number of clients. ...
3
votes
1answer
136 views

Reverse singly linked list

Description: Given a linked list reverse it and return the new head. Code: ...
0
votes
3answers
1k views

Move last node of the linked list to the front

Description: Given a linked list move the last node to the front. For example: 10 20 30 40 -> 40 10 20 30 Code: ...
-1
votes
1answer
1k views

Maximum Difference in an Array [closed]

Maintain a minimum and max difference as we scan the input array. ...
3
votes
2answers
66 views

Dutch partition

Dutch Partition problem. Partition the given array using the pivotIndex into groups with elements smaller than the pivot, equal to pivot and larger than the pivot. ...
2
votes
2answers
169 views

Naive string compression

Description: Implement a method to perform basic compression using counts of repeated characters. If the compressed string is not smaller then return the original string. Code: ...
3
votes
1answer
289 views

Check if two strings are permutations of each other

Description: Given two strings check if those two are permutation of each other. Its expected that input string can contain ASCII characters. Code: ...
1
vote
1answer
78 views

Find GCD of two numbers without using multiplication, division or modulus operators

If either a or b is 0 return the other number. If both even return gcd of a/2 and b/2. If either a or b is even divide it by 2 and return gcd of the pair. If a less than or equal to b, return the gcd ...
2
votes
0answers
482 views

Three sum using binary search

Given an array and a value, find all the triplets in the array whose sum is equal to the given value. For example, if the given array is {12, 3, 4, 1, 6, 9} and the ...
0
votes
1answer
68 views

Generate power sets given a set of elements in java

For an array of length n, the possible number of subsets is Math.pow(2, n). for each value between 0 and Math.pow(2, n), see the index at which the bit is set, and include the corresponding number in ...
3
votes
2answers
2k views

Check if the given string has duplicates

Description: Given a string find if it contains duplicate characters. The string contains only ASCII characters. Code: ...