Turing Coding Interview Questions

Valid Parentheses

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

Longest Substring Without Repeating Characters

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

Baseball Game

You are keeping the scores for a baseball game with strange rules. At the beginning of the game, you start with an empty record.

Minimum Cost For Tickets

You have planned some train traveling one year in advance. The days of the year in which you will travel are given as an integer array days. Each day is an inte...

Koko Eating Bananas

Koko loves to eat bananas. There are n piles of bananas, the ith pile has piles[i] bananas. The guards have gone and will come back in h hours.

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.

Longest Common Prefix

Write a function to find the longest common prefix string amongst an array of strings.

Validate IP Address

Given a string queryIP, return "IPv4" if IP is a valid IPv4 address, "IPv6" if IP is a valid IPv6 address or "Neither" if IP is not a correct IP of any type.

Find the Town Judge

In a town, there are n people labeled from 1 to n. There is a rumor that one of these people is secretly the town judge.

Minimum Length of Anagram Concatenation

You are given a string s, which is known to be a concatenation of anagrams of some string t.

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...

Maximum Subarray

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

Apply Operations to Make Sum of Array Greater Than or Equal to k

You are given a positive integer k. Initially, you have an array nums = [1].

Climbing Stairs

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

Find Duplicate File in System

Given a list paths of directory info, including the directory path, and all the files with contents in this directory, return all the duplicate files in the fil...

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...

Product of Array Except Self

Given an integer array nums, return an array answer such that answer[i] is equal to the product of all the elements of nums except nums[i].

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.

Partition Array Into Three Parts With Equal Sum

Given an array of integers arr, return true if we can partition the array into three non-empty parts with equal sums.

Maximum Number of Vowels in a Substring of Given Length

Given a string s and an integer k, return the maximum number of vowel letters in any substring of s with length k.

Regular Expression Matching

Given an input string s and a pattern p, implement regular expression matching with support for '.' and '' where:

Longest Consecutive Sequence

Given an unsorted array of integers nums, return the length of the longest consecutive elements sequence.

Find All Anagrams in a String

Given two strings s and p, return an array of all the start indices of p's anagrams in s. You may return the answer in any order.

Kth Largest Element in an Array

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

3Sum

Given an integer array nums, return all the triplets [nums[i], nums[j], nums[k]] such that i != j, i != k, and j != k, and nums[i] + nums[j] + nums[k] == 0.

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.

Longest Palindromic Substring

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

Find First and Last Position of Element in Sorted Array

Given an array of integers nums sorted in non-decreasing order, find the starting and ending position of a given target value.

Valid Palindrome

A phrase is a palindrome if, after converting all uppercase letters into lowercase letters and removing all non-alphanumeric characters, it reads the same forwa...

Group Anagrams

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

Jump Game

You are given an integer array nums. You are initially positioned at the array's first index, and each element in the array represents your maximum jump length...

Race Car

Your car starts at position 0 and speed +1 on an infinite number line. Your car can go into negative positions. Your car drives automatically according to a seq...

Maximum Repeating Substring

For a string sequence, a string word is k-repeating if word concatenated k times is a substring of sequence. The word's maximum k-repeating value is the highest...

Spiral Matrix

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

Longest Repeating Character Replacement

You are given a string s and an integer k. You can choose any character of the string and change it to any other uppercase English character. You can perform th...

Consecutive Numbers

Table: Logs

Reverse Only Letters

Given a string s, reverse the string according to the following rules:

Sum of Digit Differences of All Pairs

You are given an array nums consisting of positive integers where all integers have the same number of digits.

Minimum Number of Operations to Make Word K-Periodic

You are given a string word of size n, and an integer k such that k divides n.

Number of Subsequences That Satisfy the Given Sum Condition

You are given an array of integers nums and an integer target.

Minimum Number of Operations to Satisfy Conditions

You are given a 2D matrix grid of size m x n. In one operation, you can change the value of any cell to any non-negative number. You need to perform some operat...