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Questions tagged [interview-questions]

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

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5
votes
1answer
125 views

Call center escalation excercise, using Chain of Responsibility pattern

This is a coding interview I found online, to be solved within 30 minutes: Design an OOP concept for an application where employee can dispatch their incoming phone call according to their ...
3
votes
1answer
354 views

Merge sort Java implementation for an interview

I just learned Merge sort, and I really like this Merge sort implementation since it is very logical and very easy to follow. If I was asked in an interview to implement merge sort, will this ...
4
votes
1answer
101 views

ZigZag tree travesal

The question is taken for a coding interview I had, it is also in geeks for geeks, https://www.geeksforgeeks.org/zigzag-tree-traversal/ you are given a binary tree and you need to print it in a ...
0
votes
1answer
62 views

Nodejs Interview - API calls and exchange rate

I did an initial technical phone screening with this company which went ok, they then sent me a programming exercise to complete and send back to them. The goal of the exercise: -take input as a ...
2
votes
3answers
111 views

Three Numbers in Java

Given three positive numbers A, B, and C. Find the number of positive integers less than D that are divisible by either of A, B or C. Input format The 1st argument given is an Integer A. ...
1
vote
2answers
146 views

Subset Sums in Java

Given an array of integers, print sums of all subsets in it. Output should be printed in increasing order of sums. Input : arr[] = {2, 3} Output: 0 2 3 5 Input : ...
1
vote
3answers
2k views

Sort all even numbers in ascending order and then sort all odd numbers in Descending order Java

Given an array of integers (both odd and even), the task is to sort them in such a way that the first part of the array contains odd numbers sorted in descending order, rest portion contains even ...
2
votes
2answers
122 views

Scroll text across a fixed width

In an interview, I was asked to write code to produce this output: T TE TES TEST EST ST T The code I wrote was: ...
2
votes
1answer
138 views

Interview Take Home Challenge: Chat server

Recent take-home challenge I was assigned from a recruiter prior to technical interviews with the team. The team wanted it written in GOlang (I had no experience in the language) but told the ...
5
votes
1answer
84 views

News reading application version 2

following the answer I got from t3chb0t last time News-reading application using the Observer pattern and also following the example here https://msdn.microsoft.com/en-us/library/dd990377(v=vs.110)....
7
votes
2answers
518 views

Iterator for BFS binary tree traversal

I implemented an iterator pattern for C# using IEnumerator and IEnumerable. The goal of the implementation is to traverse a ...
5
votes
2answers
2k views

Minimum swaps algorithm terminated due to timeout

I have been trying to solve this question. Given an unordered array consisting of consecutive integers [1, 2, 3, …, n], find the minimum number of two-element swaps to sort the array. I was able ...
6
votes
2answers
195 views

Find char which appears maximal number of times

I had 15 minutes to code the following question: Given a file name return the char which appears maximal number of times. please do not take into account the unit test. Please look at the final ...
2
votes
1answer
228 views

Reverse a linked list

I was given 15 minutes to write the code to reverse a singly-linked list. What do you think of the code style here? ...
5
votes
2answers
896 views

Remove the first value for a doubly linked list

You need to remove the first element which contains a given value from a doubly linked list. I created two solutions since I find the edge case of removing the first element to be problematic. So I ...
5
votes
5answers
2k views

Sort an array of 0s, 1s and 2s in Java

Write a program to sort an array of 0's,1's and 2's in ascending order. Input: The first line contains an integer 'T' denoting the total number of test cases. In each test cases, First ...
5
votes
3answers
1k views

Are strings anagram

This is a question from the book "Cracking the Coding Interview". Write a method to decide if two strings are anagrams or not I think interviewer will not be convinced with this solution because ...
2
votes
6answers
475 views

Alone in a Couple implementation in Java

In a party everyone is in couple except one. People who are in couple have same numbers. Find out the person who is not in couple. Input: The first line contains an integer \$T\$ denoting ...
4
votes
2answers
1k views

Remove duplicate characters in a string

This is a question from the book "Cracking the Coding Interview". Design an algorithm and write code to remove the duplicate characters in a string without using any additional buffer NOTE: One ...
5
votes
4answers
341 views

In-place reverse of C-style string

This is a question from the book "Cracking the Coding Interview". Write code to reverse a C-Style String (C-String means that “abcd” is represented as five characters, including the null ...
6
votes
7answers
3k views

Check if a string has all unique characters

This is a question from the book "Cracking the Coding Interview". Implement an algorithm to determine if a string has all unique characters What if you can not use additional data structures? I ...
3
votes
1answer
2k views

Solving maze problem with backtracking solution using stack

I solved the maze backtracking question using a stack however could not find any other solution like that anywhere (to validate my solution is actually a valid one). The problem statement is as ...
2
votes
1answer
412 views

Group Anagrams Together approach in Java

Given an array of words, print the count of all anagrams together in sorted order (increasing order of counts). For example, if the given array is {“cat”, “dog”, “tac”, “god”, “act”}, then grouped ...
2
votes
1answer
69 views

Top 2 Frequent Elements in JavaScript

I got the original problem from Leetcode for top k frequent elements, But I decide to simplify the problem just top 2 elements to make it simpler to solve. ...
3
votes
1answer
310 views

Thread-safe arraylist with get, put, add, remove functions

I am preparing for multithreading interview questions and I don't have much experience with multithreading. I referred some online article to come up with a solution. Is this solution appropriate? <...
0
votes
1answer
206 views

Reversing the vowels in a String

Given a string, reverse only the vowels present in it and print the resulting string. Input: First line of the input file contains an integer T denoting the number of test ...
2
votes
1answer
102 views

Anagram checking implementation

Given two strings, check whether two given strings are anagram of each other or not. An anagram of a string is another string that contains same characters, only the order of characters can be ...
4
votes
1answer
2k views

2D Maze solver using recursion in Python

A company I interviewed for sent me a coding problem to solve. The problem was to find a solution to a maze, not necessarily the shortest one. The input would be like so: ...
15
votes
2answers
3k views

Roman to Integer

I'm trying to get better as a programmer and would love any feedback on my code. Especially the section in the while loop. How could I make this more readable? What would your opinion as an ...
5
votes
3answers
129 views

Implementing an order system for a job interview

I have to implement a relatively basic order system in Java for part of the process of a job interview. At the moment I have working code that allows for the creation, and updating of orders for an ...
3
votes
2answers
137 views

Non repeating character in Java

Given a string s consisting of lowercase Latin Letters, find the first non repeating character in s. Input: The first line contains T denoting the number of testcases. Then follows ...
2
votes
3answers
918 views

Given a sorted array nums, remove the duplicates in-place

I wrote an algorithm to solve this challenge but would love some feedback on its efficiency and, if you were an interviewer, what your opinion would be on my solution. I believe my time complexity is \...
1
vote
2answers
485 views

Find all root to leaf paths in binary tree

Description: Given a binary tree, return all root-to-leaf paths. Leetcode ...
6
votes
1answer
619 views

Calculate implied volatility for options on stocks and futures with two models

I wrote a code for a quant finance job and they told me that, besides it worked, it was poorly written. I asked for a more detailed feedback but they did not send it to me. I paste it here with ...
2
votes
1answer
602 views

Find all k-sum paths in a binary tree

Description: Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. Note: A leaf is a node with no children. Leetcode Code: ...
2
votes
1answer
218 views

Find minimum depth in a binary tree

Description: Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. Note: A leaf is a node ...
1
vote
2answers
122 views

Star Elements implementation in Java

Given an unsorted array. The task is to find all the star and super star elements in the array. Star are those elements which are strictly greater than all the elements on its right side. Super ...
6
votes
1answer
442 views

Codility: MaxZeroProduct - complexity issues

My solution scored 100% correctness, but 0% Performance. I just can't figure out how to minimize complexity time. Problem: Write a function: ...
1
vote
2answers
144 views

Greater on the right side in Java

Given an array of integers, replace every element with the next greatest element (greatest element on the right side) in the array. Since there is no element next to the last element, replace it ...
1
vote
0answers
86 views

System on Chip Validator

With reference to my source files, published in the git repository soc-testing I did my best effort at coding, based on 30 years of experience, so I would like to know what I did wrong with my ...
5
votes
0answers
147 views

Function which would get the next `n` slots from the current time [closed]

I have attended an interview recently and my coding got rejected by the panel. I am new to Python and is mentioning my code below. Please help me improve the code quality or any bug: Question: Given ...
3
votes
3answers
357 views

Inventory allocation method

Recently I have attended an Interview with a firm. They gave me a task to complete. I have done it and tested it as well. But they rejected my code. Is the given code properly written? Is my coding ...
0
votes
2answers
1k views

Count the number of occurences of X's within a range in Java

Given an integer X within the range of 0 to 9, and given two positive integers as upper and lower bounds respectively, find the number of times X occurs as a digit in an integer within the ...
1
vote
2answers
74 views

Count total set bits

Im am solving Count total set bits: Find the sum of all bits from numbers 1 to N. Input: The first line of input contains an integer T denoting the number of test cases. The first line ...
0
votes
2answers
595 views

Check if array contains contiguous integers with duplicates allowed in Java

Given an array of n integers(duplicates allowed). Print “Yes” if it is a set of contiguous integers else print “No”. INPUT: The first line consists of an integer T i.e. the number of test ...
15
votes
4answers
4k views

Checking if two strings are anagrams in Python

The code written in Python 3.6 mostly using Python's built in functions sorted and len. First I'm checking for the edge case that the two given strings are not of ...
1
vote
3answers
758 views

Reverse a sentence in Java

You are given an array of characters arr that consists of sequences of characters separated by space characters. Each space-delimited sequence of characters defines a word. Implement a function ...
2
votes
2answers
395 views

Given an integer n, generate the nth count and say sequence

I am solving interview questions from here. Problem : Given an integer n, generate the nth count and say sequence. The count-and-say sequence is the sequence of integers beginning as follows: <...
7
votes
4answers
6k views

Bank accounts with methods to transfer funds

I recently took a programming exam for an interview and unfortunately didn't pass it. I wasn't offered any feedback about the results. I'm looking for help on how to improve my OOP skills. The ...
3
votes
0answers
440 views

Find redundant braces in an input string

I am solving interview questions from here. Problem : Write a program to validate if the input string has redundant braces Return 0/1 : ...