[题解]Palindrome pairs [Codeforces159D] 传送门:\(Palindrome\) \(pairs\) \([CF159D]\) [题目描述] 给定一个长度为 \(N\) 的字符串 \(S\),求有多少四元组 \((l_1,r_1,l_2,r_2)\) 满足 \(1 \leqslant l_1 \leqslant r_1 \leqslant l_2 \leqslant r_2 \leqslant N\) 且 \(S[l1...r1],\) \([Sl2...r2]\…

前言   [LeetCode 题解]系列传送门:  http://www.cnblogs.com/double-win/category/573499.html   1.题目描述 Determine whether an integer is a palindrome. Do this without extra space. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of c…

9. Palindrome Number 题目: Determine whether an integer is a palindrome. Do this without extra space. click to show spoilers. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of converting the integer to string, note the…

我现在在做一个叫<leetbook>的开源书项目,把解题思路都同步更新到github上了,需要的同学可以去看看 地址:https://github.com/hk029/leetcode 这个是书的地址:https://hk029.gitbooks.io/leetbook/ 009. Palindrome Number[E] 问题: Determine whether an integer is a palindrome. Do this without extra space. 思路 这里说不…

Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example,"A man, a plan, a canal: Panama" is a palindrome."race a car" is not a palindrome. Note:Have you consider that th…

https://leetcode.com/problems/valid-palindrome/ 题目: Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example,"A man, a plan, a canal: Panama" is a palindrome."race a car"…

http://codeforces.com/contest/344/problem/B #include <cstdio> #include <cstring> using namespace std; int main() { int a,b,c; ,t2=,t3=; while(scanf("%d%d%d",&a,&b,&c)!=EOF) { bool flag=false; ; i<=a; i++) { t1=i; ) { t…

Examples Input 10 5abacdabcda7 10 05 8 11 4 03 6 07 10 1 Output cbcaaaabdd Input 10 1agjucbvdfk1 10 1 Output abcdfgjkuv 题意:给定一个字符串,长度为n,q次操作,对于每次操作,但flag为1时,l——r为非减序列,当flag为0时,l——r为非增序列. 输出q次操作后的字符串. 思路:考虑记数排序,这样时间复杂度为26nlogn. #include<cstdio> #incl…

我居然每道题都能想出来 虽然不是每道题都能写对,debug了很久/facepalm C - Many Medians 排序后前N/2个数的中位数时排序后第N/2 + 1的数 其余的中位数都是排序后第N / 2的数 #include <iostream> #include <cstdio> #include <vector> #include <set> #include <cstring> #include <string> #inc…

题目链接:http://codeforces.com/problemset/problem/675/D 题意:给一个由n个互异整数组成的序列a[],模拟BST的插入过程,依次输出每插入一个元素a[i]后a[i]的父节点. 数据范围:n [2, 10^5] 思路:直接模拟一般的BST而不维护平衡性的话,有可能会出现极度不平衡甚至退化的情况,复杂度会从O(nlogn)上升到O(n^2).因此要用平衡二叉树. 可以利用STL中的set容器,但对于题目所要找的“父节点”,set并不提供接口.这时就要考察…