RockPaperProgrammer

Write a program to find the node at which the intersection of two singly linked lists begins.For example, the following two linked lists:A: a1 → a2 ↘

Reverse digits of an integer.Example1: x = 123, return 321Example2: x = -123, return -321TagMath------------------------------------------------------------------------------------------

Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.For example,"A man, a plan, a canal: Panama" is a palindrome."race a car" is not a

Implement strStr().Returns the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.TagsTwo Pointers, String------------------------------------

Given two binary strings, return their sum (also a binary string).For example,a = "11"b = "1"Return "100".TagMath, String-------------------------------------------------------------

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

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.Example:Given nums =

Implement atoi to convert a string to an integer.Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input ca

Determine if a Sudoku is valid, according to: Sudoku Puzzles - The Rules.The Sudoku board could be partially filled, where empty cells are filled with the character '.'.A partially fille

Given an array of integers and an integer k, find out whether there are two distinct indices i and j in the array such that nums[i] = nums[j] and the difference between i and j is at most k.

Given an integer n, return the number of trailing zeroes in n!.Note: Your solution should be in logarithmic time complexity.Credits:Special thanks to @ts for adding this problem and creating

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.TagsBFS, DFS, Tree--------

Implement the following operations of a stack using queues.push(x) -- Push element x onto stack.pop() -- Removes the element on top of the stack.top() -- Get the top element.empty() -- Return whet

Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum.For example:Given the below binary tree and sum

Determine whether an integer is a palindrome. Do this without extra space.TagsMath----------------------------------------------------------------------------------------------------------

Given an index k, return the kth row of the Pascal's triangle.For example, given k = 3,Return [1,3,3,1].Note:Could you optimize your algorithm to use only O(k) extra space?TagsArray

You are a product manager and currently leading a team to develop a new product. Unfortunately, the latest version of your product fails the quality check. Since each version is developed based on the

Given an integer array nums, find the sum of the elements between indices i and j (i ≤ j), inclusive.Example:Given nums = [-2, 0, 3, -5, 2, -1]sumRange(0, 2) -> 1sumRange(2, 5) -> -1sumRan

Given a positive integer, return its corresponding column title as appear in an Excel sheet.For example: 1 -> A 2 -> B 3 -> C ... 26 -> Z 27 -> AA 28 -> AB Credits

Rotate an array of n elements to the right by k steps.For example, with n = 7 and k = 3, the array [1,2,3,4,5,6,7] is rotated to [5,6,7,1,2,3,4].Note:Try to come up as many solutions as yo

You are playing the following Bulls and Cows game with your friend: You write down a number and ask your friend to guess what the number is. Each time your friend makes a guess, you provide a hint t

Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array.Note:You may assume that nums1 has enough space (size that is greater or equal to m + n) to hold addit

Given two strings s and t, determine if they are isomorphic.Two strings are isomorphic if the characters in s can be replaced to get t.All occurrences of a character must be replaced with anot

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

Given a pattern and a string str, find if str follows the same pattern.Here follow means a full match, such that there is a bijection between a letter in pattern and a non-empty word in str.

Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string.If the last word does not exist, return 0.Note: A word is

The count-and-say sequence is the sequence of integers beginning as follows:1, 11, 21, 1211, 111221, ...1 is read off as "one 1" or 11.11 is read off as "two 1s" or 21.21 is read off as 

Given a binary tree, return all root-to-leaf paths.For example, given the following binary tree: 1 / \2 3 \ 5All root-to-leaf paths are:["1->2->5", "1->3"]Cre

Given a binary tree, return all root-to-leaf paths.For example, given the following binary tree: 1 / \2 3 \ 5All root-to-leaf paths are:["1->2->5", "1->3"]Cre

Remove all elements from a linked list of integers that have value val.ExampleGiven: 1 --> 2 --> 6 --> 3 --> 4 --> 5 --> 6, val = 6Return: 1 --> 2 --> 3 --> 4 --> 5Credits:Special thanks

Given a singly linked list, determine if it is a palindrome.Follow up:Could you do it in O(n) time and O(1) space?Subscribe to see which companies asked this questionTagLinkedList, T

Description:Count the number of prime numbers less than a non-negative number, n.Credits:Special thanks to @mithmatt for adding this problem and creating all test cases.TagsHash Table,

The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)P A H NA P L S I

Compare two version numbers version1 and version2.If version1 > version2 return 1, if version1 version2 return -1, otherwise return 0.You may assume that the version strings are non-empty and co

Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level).For example:Given binary tree [3,9,20,null,null,15,7], 3 / \ 9 2

Given a sorted array, remove the duplicates in place such that each element appear only once and return the new length.Do not allocate extra space for another array, you must do this in place with

Given numRows, generate the first numRows of Pascal's triangle.For example, given numRows = 5,Return[ [1], [1,1], [1,2,1], [1,3,3,1], [1,4,6,4,1]]TagsArray----

Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST.According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined betw

Given a roman numeral, convert it to an integer.Input is guaranteed to be within the range from 1 to 3999.Tags:Math, String-------------------------------------------------------------

Reverse a singly linked list.TagsLinkedList-------------------------------------------------------------------------------------------------------------------------------------------------