原题链接:http://www.spoj.com/problems/SUPPER/ 这道题n<=200000,那么确定为nlogn的算法,再定位到求LIS的O(nlogn)的算法. 对于每个a[i],求出其向左能延伸的元素个数L[i]和向右能延伸的元素个数R[i],所有位置L[i]+R[i]为最大值的元素排序输出即可. 心得: 1.求LIS的O(nlogn)算法能解决子区间的LIS问题,所以经常出现在题目中,要灵活运用. 2.lower_bound函数有cmp函数参数可以选择升序查找(less<…

Discription John likes playing the game Permutation Jumping. First he writes down a permutation A of the first n numbers. Then, he chooses any cell to start on. If he is currently at cell x and hasnt visited the cell A[x], he jumps to cell A[x]. He k…

题意 给出一个长度为n的,所有元素大小在[1,n]的整数数列,要求选出一个尽量长的区间使得区间内所有元素组成一个1到区间长度k的排列,输出k的最大值 n<=1e5 分析 不会做,好菜啊.jpg 学习了西方那一套理论,里面别人的题解写得挺吼的但是没多少人点赞23333. 外来的和尚好念经 一个合法排列必然包括一个1.那么我们可以枚举这个1的位置,既然包含了这个1就不能包含其他的1,所以我们可以找出这个1左边的第一个1的位置L(如果没有就是0)和右边的第一个1的位置R(如果没有就是n+1).包括这个…

2588: Spoj 10628. Count on a tree Time Limit: 12 Sec  Memory Limit: 128 MBSubmit: 5217  Solved: 1233[Submit][Status][Discuss] Description 给定一棵N个节点的树,每个点有一个权值,对于M个询问(u,v,k),你需要回答u xor lastans和v这两个节点间第K小的点权.其中lastans是上一个询问的答案,初始为0,即第一个询问的u是明文. Input 第一…

The set [1,2,3,-,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order,We get the following sequence (ie, for n = 3): "123" "132" "213" "231" "312" "3…

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…

Given a string, determine if a permutation of the string could form a palindrome. For example,"code" -> False, "aab" -> True, "carerac" -> True. Hint: Consider the palindromes of odd vs even length. What difference d…

The set [1,2,3,…,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order,We get the following sequence (ie, for n = 3): "123" "132" "213" "231" "312" "3…

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…

The set [1,2,3,-,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order,We get the following sequence (ie, for n = 3): "123" "132" "213" "231" "312" "3…