J.P. Morgan Coding Interview Questions

Sort Integers by The Number of 1 Bits

You are given an integer array arr. Sort the integers in the array in ascending order by the number of 1's in their binary representation and in case of two or...

Reaching Points

Given four integers sx, sy, tx, and ty, return true if it is possible to convert the point (sx, sy) to the point (tx, ty) through some operations, or false othe...

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.

Minimum Suffix Flips

You are given a 0-indexed binary string target of length n. You have another binary string s of length n that is initially set to all zeros. You want to make s...

Remove Colored Pieces if Both Neighbors are the Same Color

There are n pieces arranged in a line, and each piece is colored either by 'A' or by 'B'. You are given a string colors of length n where colors[i] is the color...

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...

Next Permutation

A permutation of an array of integers is an arrangement of its members into a sequence or linear order.

Minimum Absolute Difference

Given an array of distinct integers arr, find all pairs of elements with the minimum absolute difference of any two elements.

Check Whether Two Strings are Almost Equivalent

Two strings word1 and word2 are considered almost equivalent if the differences between the frequencies of each letter from 'a' to 'z' between word1 and word2 i...

Group Anagrams

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

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.

Numbers With Repeated Digits

Given an integer n, return the number of positive integers in the range [1, n] that have at least one repeated digit.

Determine Color of a Chessboard Square

You are given coordinates, a string that represents the coordinates of a square of the chessboard. Below is a chessboard for your reference.

Minimum Swaps to Make Strings Equal

You are given two strings s1 and s2 of equal length consisting of letters "x" and "y" only. Your task is to make these two strings equal to each other. You can...

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...

Valid Parentheses

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

Reverse Odd Levels of Binary Tree

Given the root of a perfect binary tree, reverse the node values at each odd level of the tree.

Lexicographically Smallest String After a Swap

Given a string s containing only digits, return the lexicographically smallest string that can be obtained after swapping adjacent digits in s with the same par...

Lexicographically Smallest String After Applying Operations

You are given a string s of even length consisting of digits from 0 to 9, and two integers a and b.

Maximum Number of Points From Grid Queries

You are given an m x n integer matrix grid and an array queries of size k.

Check if Number Has Equal Digit Count and Digit Value

You are given a 0-indexed string num of length n consisting of digits.

Display Table of Food Orders in a Restaurant

Given the array orders, which represents the orders that customers have done in a restaurant. More specifically orders[i]=[customerNamei,tableNumberi,foodItemi]...

Button With Longest Push Time

You are given a 2D array events which represents a sequence of events where a child pushes a series of buttons on a keyboard. Each events[i] = [indexi, timei] i...

Rotate Image

You are given an n x n 2D matrix representing an image, rotate the image by 90 degrees (clockwise).

Find Resultant Array After Removing Anagrams

You are given a 0-indexed string array words, where words[i] consists of lowercase English letters.

Longest Palindromic Substring

Given a string s, return the longest palindromic substring in s.

Count Numbers with Unique Digits

Given an integer n, return the count of all numbers with unique digits, x, where 0 <= x < 10n.

Longest Substring Without Repeating Characters

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

Happy Number

Write an algorithm to determine if a number n is happy.

Maximum Product of Two Elements in an Array

Given the array of integers nums, you will choose two different indices i and j of that array. Return the maximum value of (nums[i]-1)(nums[j]-1).

Climbing Stairs

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

Generate Parentheses

Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.

Best Time to Buy and Sell Stock II

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

Two Sum

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

Maximum Subarray

Given an integer array nums, find the subarray with the largest sum, and return its sum.

Fizz Buzz

Given an integer n, return a string array answer (1-indexed) where:

Maximum Units on a Truck

You are assigned to put some amount of boxes onto one truck. You are given a 2D array boxTypes, where boxTypes[i] = [numberOfBoxesi, numberOfUnitsPerBoxi]:

Intersection of Two Arrays

Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must be unique and you may return the result in any...

Minimum Operations to Make All Array Elements Equal

You are given an array nums consisting of positive integers.

Rearrange Array to Maximize Prefix Score

You are given a 0-indexed integer array nums. You can rearrange the elements of nums to any order (including the given order).

Subarray Sum Equals K

Given an array of integers nums and an integer k, return the total number of subarrays whose sum equals to k.

Coin Change

You are given an integer array coins representing coins of different denominations and an integer amount representing a total amount of money.

LRU Cache

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

Non-overlapping Intervals

Given an array of intervals intervals where intervals[i] = [starti, endi], return the minimum number of intervals you need to remove to make the rest of the int...

Minimum Cost to Make Array Equal

You are given two 0-indexed arrays nums and cost consisting each of n positive integers.

Binary Tree Right Side View

Given the root of a binary tree, imagine yourself standing on the right side of it, return the values of the nodes you can see ordered from top to bottom.

Pascal's Triangle

Given an integer numRows, return the first numRows of Pascal's triangle.

Reverse Linked List

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

Fibonacci Number

The Fibonacci numbers, commonly denoted F(n) form a sequence, called the Fibonacci sequence, such that each number is the sum of the two preceding ones, startin...

Daily Temperatures

Given an array of integers temperatures represents the daily temperatures, return an array answer such that answer[i] is the number of days you have to wait aft...

Palindrome Number

Given an integer x, return true if x is a palindrome, and false otherwise.

Kth Largest Element in an Array

Given an integer array nums and an integer k, return the kth largest element in the array.

Spiral Matrix

Given an m x n matrix, return all elements of the matrix in spiral order.

Shuffle an Array

Given an integer array nums, design an algorithm to randomly shuffle the array. All permutations of the array should be equally likely as a result of the shuffl...

Letter Combinations of a Phone Number

Given a string containing digits from 2-9 inclusive, return all possible letter combinations that the number could represent. Return the answer in any order.

Decode Ways

You have intercepted a secret message encoded as a string of numbers. The message is decoded via the following mapping:

Combination Sum

Given an array of distinct integers candidates and a target integer target, return a list of all unique combinations of candidates where the chosen numbers sum...

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.

Cherry Pickup

You are given an n x n grid representing a field of cherries, each cell is one of three possible integers.

Search Suggestions System

You are given an array of strings products and a string searchWord.

Find the Duplicate Number

Given an array of integers nums containing n + 1 integers where each integer is in the range [1, n] inclusive.

Top K Frequent Elements

Given an integer array nums and an integer k, return the k most frequent elements. You may return the answer in any order.

Open the Lock

You have a lock in front of you with 4 circular wheels. Each wheel has 10 slots: '0', '1', '2', '3', '4', '5', '6', '7', '8', '9'. The wheels can rotate freely...

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.

Count Binary Substrings

Given a binary string s, return the number of non-empty substrings that have the same number of 0's and 1's, and all the 0's and all the 1's in these substrings...

Two Sum II - Input Array Is Sorted

Given a 1-indexed array of integers numbers that is already sorted in non-decreasing order, find two numbers such that they add up to a specific target number....

Integer to Roman

Seven different symbols represent Roman numerals with the following values:

Contains Duplicate

Given an integer array nums, return true if any value appears at least twice in the array, and return false if every element is distinct.

Find Occurrences of an Element in an Array

You are given an integer array nums, an integer array queries, and an integer x.

Permutations

Given an array nums of distinct integers, return all the possible permutations. You can return the answer in any order.

Minimum String Length After Removing Substrings

You are given a string s consisting only of uppercase English letters.

Minimum Insertions to Balance a Parentheses String

Given a parentheses string s containing only the characters '(' and ')'. A parentheses string is balanced if:

Ugly Number

An ugly number is a positive integer which does not have a prime factor other than 2, 3, and 5.

Sum of Subarray Ranges

You are given an integer array nums. The range of a subarray of nums is the difference between the largest and smallest element in the subarray.

Average Time of Process per Machine

Table: Activity

Container With Most Water

You are given an integer array height of length n. There are n vertical lines drawn such that the two endpoints of the ith line are (i, 0) and (i, height[i]).