Next Permutation Given a list of integers, which denote a permutation. Find the next permutation in ascending order. Notice The list may contains duplicate integers. Example For [1,3,2,3], the next permutation is [1,3,3,2] For [4,3,2,1], the next per…

1053. Previous Permutation With One Swap https://leetcode.com/problems/previous-permutation-with-one-swap/ 题意:Given an array A of positive integers (not necessarily distinct), return the lexicographically largest permutation that is smaller than A, t…

LeetCode 31 Next Permutation / 60 Permutation Sequence [Permutation] <c++> LeetCode 31 Next Permutation 给出一个序列,求其下一个排列 STL中有std::next_permutation这个方法可以直接拿来用 也可以写一个实现程序: 从右往左遍历序列,找到第一个nums[i-1]<num[i]的位置,记p = i-1. 如果第一步没有找到,说明整个序列满足单调递减,也就是最大的排列,那…

A reverse version of the Dictionary algorithm :) If you AC-ed "Next Permutation II", copy it over and just reverse the conditions. class Solution { public: /** * @param nums: An array of integers * @return: An array of integers that's previous p…

Similar to next permutation, the steps as follow: 1) Find k in the increasing suffix such that nums[k] > nums[k+1], if there is no such element, the permutation is the smallest like [0, 1, 2,... n], reverse it, we can get the previous permutaton. 2)…

题目如下: Given an array A of positive integers (not necessarily distinct), return the lexicographically largest permutation that is smaller than A, that can be made with one swap (A swap exchanges the positions of two numbers A[i] and A[j]).  If it cann…

题目 上一个排列 给定一个整数数组来表示排列,找出其上一个排列. 样例 给出排列[1,3,2,3],其上一个排列是[1,2,3,3] 给出排列[1,2,3,4],其上一个排列是[4,3,2,1] 注意 排列中可能包含重复的整数 解题 排列的特征 123 的排列依次是:123.132.213.231.312.321 要点: 1.整体来说是升序的 2.对一个数而言,各位数字中,大的数字越靠后,这个数在排列的位置越靠前,同样,小的数字越靠前,这个数在排列的位置越靠前 参考1 参考2 上面说的方法好像都…

Given a string s, return all the palindromic permutations (without duplicates) of it. Return an empty list if no palindromic permutation could be form. For example: Given s = "aabb", return ["abba", "baab"]. Given s = "a…

题目: 排列序号 给出一个不含重复数字的排列,求这些数字的所有排列按字典序排序后该排列的编号.其中,编号从1开始. 样例 例如,排列[1,2,4]是第1个排列. 解题: 这个题目感觉很坑的.感觉这只有求出所有的排列,然后找出其对应的下标,但是怎么求出排列,在做Project Euler 时候碰到过,但是现在我又不会写了,那时候毕竟是抄别人的程序的.在geekviewpoint看到一种很厉害的解法,不需要求所有的排列,直接根据给的数组进行求解. 思路: 1.对于四位数:4213 = 4*100+2…

E. Square Root of Permutation A permutation of length n is an array containing each integer from 1 to n exactly once. For example, q = [4, 5, 1, 2, 3] is a permutation. For the permutation q the square of permutation is the permutation p that p[i] = …