Expedia Coding Interview Questions

Find the Smallest Divisor Given a Threshold

Given an array of integers nums and an integer threshold, we will choose a positive integer divisor, divide all the array by it, and sum the division's result....

Valid Triangle Number

Given an integer array nums, return the number of triplets chosen from the array that can make triangles if we take them as side lengths of a triangle.

The kth Factor of n

You are given two positive integers n and k. A factor of an integer n is defined as an integer i where n % i == 0.

String Compression

Given an array of characters chars, compress it using the following algorithm:

Valid Word

A word is considered valid if:

Minimum One Bit Operations to Make Integers Zero

Given an integer n, you must transform it into 0 using the following operations any number of times:

Break a Palindrome

Given a palindromic string of lowercase English letters palindrome, replace exactly one character with any lowercase English letter so that the resulting string...

Divide Players Into Teams of Equal Skill

You are given a positive integer array skill of even length n where skill[i] denotes the skill of the ith player. Divide the players into n / 2 teams of size 2...

Minimum Replacements to Sort the Array

You are given a 0-indexed integer array nums. In one operation you can replace any element of the array with any two elements that sum to it.

Rearrange Words in a Sentence

Given a sentence text (A sentence is a string of space-separated words) in the following format:

Most Visited Sector in a Circular Track

Given an integer n and an integer array rounds. We have a circular track which consists of n sectors labeled from 1 to n. A marathon will be held on this track,...

Valid Parentheses

Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

Remove Duplicate Letters

Given a string s, remove duplicate letters so that every letter appears once and only once. You must make sure your result is the smallest in lexicographical or...

Longest Substring Without Repeating Characters

Given a string s, find the length of the longest substring without duplicate characters.

Best Time to Buy and Sell Stock

You are given an array prices where prices[i] is the price of a given stock on the ith day.

Group Anagrams

Given an array of strings strs, group the anagrams together. You can return the answer in any order.

Trapping Rain Water

Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it can trap after raining.

Set Matrix Zeroes

Given an m x n integer matrix matrix, if an element is 0, set its entire row and column to 0's.

Capacity To Ship Packages Within D Days

A conveyor belt has packages that must be shipped from one port to another within days days.

Find the City With the Smallest Number of Neighbors at a Threshold Distance

There are n cities numbered from 0 to n-1. Given the array edges where edges[i] = [fromi, toi, weighti] represents a bidirectional and weighted edge between cit...

Minimum Number of Swaps to Make the String Balanced

You are given a 0-indexed string s of even length n. The string consists of exactly n / 2 opening brackets '[' and n / 2 closing brackets ']'.

Max Consecutive Ones III

Given a binary array nums and an integer k, return the maximum number of consecutive 1's in the array if you can flip at most k 0's.

Roman to Integer

Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M.

House Robber

You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from rob...

Jump Game II

You are given a 0-indexed array of integers nums of length n. You are initially positioned at index 0.

Number of Islands

Given an m x n 2D binary grid grid which represents a map of '1's (land) and '0's (water), return the number of islands.

Degree of an Array

Given a non-empty array of non-negative integers nums, the degree of this array is defined as the maximum frequency of any one of its elements.

Subarray Sums Divisible by K

Given an integer array nums and an integer k, return the number of non-empty subarrays that have a sum divisible by k.

Number of Visible People in a Queue

There are n people standing in a queue, and they numbered from 0 to n - 1 in left to right order. You are given an array heights of distinct integers where heig...

Reverse Linked List

Given the head of a singly linked list, reverse the list, and return the reversed list.

Longest Increasing Subsequence

Given an integer array nums, return the length of the longest strictly increasing subsequence.

Add Two Numbers

You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order, and each of their nodes contains a sing...

Merge Sorted Array

You are given two integer arrays nums1 and nums2, sorted in non-decreasing order, and two integers m and n, representing the number of elements in nums1 and num...

Merge Intervals

Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the non-overlapping intervals that cove...

Climbing Stairs

You are climbing a staircase. It takes n steps to reach the top.

Two Sum

Given an array of integers nums and an integer target, return the indices of the two numbers that add up to target.

Least Number of Unique Integers after K Removals

Given an array of integers arr and an integer k. Find the least number of unique integers after removing exactly k elements.

Count Number of Pairs With Absolute Difference K

Given an integer array nums and an integer k, return the number of pairs (i, j) where i < j such that |nums[i] - nums[j]| == k.

Minimum Number of Chairs in a Waiting Room

You are given a string s. Simulate events at each second i:

Keys and Rooms

There are n rooms labeled from 0 to n - 1 and all the rooms are locked except for room 0. Your goal is to visit all the rooms. However, you cannot enter a locke...

Permutation in String

Given two strings s1 and s2, return true if s2 contains a permutation of s1, or false otherwise.

Rotting Oranges

You are given an m x n grid where each cell can have one of three values:

LRU Cache

Design a data structure that follows the constraints of a Least Recently Used (LRU) cache.

Find the Index of the First Occurrence in a String

Given two strings needle and haystack, return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.

Reformat Date

Given a date string in the form Day Month Year, where: