You are given two non-empty linked lists representing two non-negative integers. The most significant digit comes first and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

Given strings S and T, find the minimum (contiguous) substring W of S, so that T is a subsequence of W.

In an election, the i-th vote was cast for persons[i] at time times[i].

Two strings X and Y are similar if we can swap two letters (in different positions) of X, so that it equals Y.

In this problem, a tree is an undirected graph that is connected and has no cycles.

We have a grid of 1s and 0s; the 1s in a cell represent bricks. A brick will not drop if and only if it is directly connected to the top of the grid, or at least one of its (4-way) adjacent bricks will not drop.

Given a list of daily temperatures T, return a list such that, for each day in the input, tells you how many days you would have to wait until a warmer temperature. If there is no future day for which this is possible, put 0 instead.

Definition of a complete binary tree from Wikipedia:In a complete binary tree every level, except possibly the last, is completely filled, and all nodes in the last level are as far left as possible. It can have between 1 and 2h nodes inclusive at the last level h.

Given a 01 matrix M, find the longest line of consecutive one in the matrix. The line could be horizontal, vertical, diagonal or anti-diagonal.Example:Input:[[0,1,1,0], [0,1,1,0], [0,0,0,1]]Output: 3Hint: The number of elements in the given matrix will not exceed 10,000.

Now she wants to rearrange the cards into groups so that each group is size W, and consists of W consecutive cards.

There are N workers. The i-th worker has a quality[i] and a minimum wage expectation wage[i].

Given two strings A and B of lowercase letters, return true if and only if we can swap two letters in A so that the result equals B.

We have a list of bus routes. Each routes[i] is a bus route that the i-th bus repeats forever. For example if routes[0] = [1, 5, 7], this means that the first bus (0-th indexed) travels in the sequence 1->5->7->1->5->7->1->... forever.

Every email consists of a local name and a domain name, separated by the @ sign.

Given n balloons, indexed from 0 to n-1. Each balloon is painted with a number on it represented by array nums. You are asked to burst all the balloons. If the you burst balloon i you will get nums[left] nums[i] nums[right] coins. Here left and right are adjacent indices of i. After the burst, th...

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 that indicates how many digits in said guess match your secret number exactly in both digit and posi...

Given a linked list and a value x, partition it such that all nodes less than x come before nodes greater than or equal to x.

On a 2D plane, we place stones at some integer coordinate points. Each coordinate point may have at most one stone.

You are given an integer array nums and you have to return a new counts array. The counts array has the property where counts[i] is the number of smaller elements to the right of nums[i].

There is a ball in a maze with empty spaces and walls. The ball can go through empty spaces by rolling up, down, left or right, but it won't stop rolling until hitting a wall. When the ball stops, it could choose the next direction.

Design a Tic-tac-toe game that is played between two players on a n x n grid.

Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below.

Given a binary search tree (BST) with duplicates, find all the mode(s) (the most frequently occurred element) in the given BST.

Given a binary tree, write a function to get the maximum width of the given tree. The width of a tree is the maximum width among all levels. The binary tree has the same structure as a full binary tree, but some nodes are null.

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down).

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down).

Return the length of the shortest, non-empty, contiguous subarray of A with sum at least K.

Given an array of n positive integers and a positive integer s, find the minimal length of a contiguous subarray of which the sum ≥ s. If there isn't one, return 0 instead.

Given a node from a cyclic linked list which is sorted in ascending order, write a function to insert a value into the list such that it remains a cyclic sorted list. The given node can be a reference to any single node in the list, and may not be necessarily the smallest value in the cyclic list.

Given an integer array, your task is to find all the different possible increasing subsequences of the given array, and the length of an increasing subsequence should be at least 2 .