摘要：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 l 阅读全文

摘要：Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary). You may assume that the intervals were initia 阅读全文

摘要：【题目】 There are N children standing in a line. Each child is assigned a rating value. You are giving candies to these children subjected to the followi 阅读全文

摘要：Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction 阅读全文

摘要：Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may comple 阅读全文

摘要：Given a string S and a string T, count the number of distinct subsequences of S which equals T. A subsequence of a string is a new string which is for 阅读全文

摘要：Given two words word1 and word2, find the minimum number of steps required to convert word1 to word2. (each operation is counted as 1 step.) You have 阅读全文

摘要：Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining. 阅读全文

摘要：Given a non-empty string s and a dictionary wordDict containing a list of non-empty words, add spaces in s to construct a sentence where each word is 阅读全文

摘要：Write a program to solve a Sudoku puzzle by filling the empty cells. Empty cells are indicated by the character '.'. You may assume that there will be 阅读全文

摘要：题目： The n-queens puzzle is the problem of placing n queens on an n×n chessboard such that no two queens attack each other. Given an integer n, return 阅读全文

摘要：Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maxim 阅读全文

摘要：Sort a linked list in O(n log n) time using constant space complexity. 题目要求使用O(nlogn)时间复杂度，可以考虑使用归并排序，在 merge two sorted lists 中，已经知道了将两个有序链表进行合并。这里只要 阅读全文

摘要：Given a singly linked list L: L0→L1→…→Ln-1→Ln,reorder it to: L0→Ln→L1→Ln-1→L2→Ln-2→… You must do this in-place without altering the nodes' values. For 阅读全文

摘要：Sort a linked list using insertion sort. 对于数组的插入排序，可以参看排序算法入门之插入排序（java实现），遍历每个元素，然后相当于把每个元素插入到前面已经排好序的数组里，对于数组，只要当前元素比前一个元素小，则前一个元素后移，然后继续跟再前面的元素比。 对 阅读全文

摘要：输入一个复杂链表（每个节点中有节点值，以及两个指针，一个指向下一个节点，另一个特殊指针指向任意一个节点），返回结果为复制后复杂链表的head。（注意，输出结果中请不要返回参数中的节点引用，否则判题程序会直接返回空） 第一种方法：使用map存放原节点和其复制节点。然后再给复制节点的next/rando 阅读全文

摘要：Gas Station There are N gas stations along a circular route, where the amount of gas at station i is gas[i]. You have a car with an unlimited gas tank 阅读全文

摘要：Given a string s and a dictionary of words dict, determine if s can be segmented into a space-separated sequence of one or more dictionary words.For e 阅读全文

摘要：Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is the root-to-leaf path 1->2->3 whic 阅读全文

摘要：Evaluate the value of an arithmetic expression in Reverse Polish Notation. Valid operators are +, -, *, /. Each operand may be an integer or another e 阅读全文