Next Permutation  Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers. If such arrangement is not possible, it must rearrange it as the lowest possible order (ie, sorted in ascending ord…

Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers. If such arrangement is not possible, it must rearrange it as the lowest possible order (ie, sorted in ascending order). The replaceme…

Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers. If such arrangement is not possible, it must rearrange it as the lowest possible order (ie, sorted in ascending order). The replaceme…

对当前排列从后向前扫描,找到一对为升序的相邻元素,记为i和j(i < j).如果不存在这样一对为升序的相邻元素,则所有排列均已找到,算法结束:否则,重新对当前排列从后向前扫描,找到第一个大于i的元素k,交换i和k,然后对从j开始到结束的子序列反转,则此时得到的新排列就为下一个字典序排列.这种方式实现得到的所有排列是按字典序有序的,这也是C++ STL算法next_permutation的思想.…

Given a collection of integers that might contain duplicates, nums, return all possible subsets. Note: Elements in a subset must be in non-descending order. The solution set must not contain duplicate subsets. For example, If nums = [1,2,2], a soluti…

Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers. If such arrangement is not possible, it must rearrange it as the lowest possible order (ie, sorted in ascending order). The replaceme…

Given an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order red, white and blue. Here, we will use the integers 0, 1, and 2 to represent the color red, white, and bl…

Swap Nodes in Pairs  Given a linked list, swap every two adjacent nodes and return its head. For example, Given 1->2->3->4, you should return the list as 2->1->4->3. Your algorithm should use only constant space. You may not modify the v…

Given a string s1, we may represent it as a binary tree by partitioning it to two non-empty substrings recursively. Below is one possible representation of s1 = "great": great / \ gr eat / \ / \ g r e at / \ a t To scramble the string, we may ch…

Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing all ones and return its area. 思路:此题的意思是给一个为0或1的矩阵,求所有为1组成的最大矩阵的面积. 此题能够巧妙转化为求最大直方图面积的问题. public class Solution { //其思想是将每一列的1逐行相加,遇0为0.遇1相加 //然后转化为求每一行的最大直方图面积的求解…