http://codeforces.com/group/1EzrFFyOc0/contest/706/problem/D 题目:就是有3种操作 + x向集合里添加 x - x 删除x元素,(保证存在 ? x 查询 x |  集合中元素的最大值 思路:就是利用字典树,从高位到低位进行贪心. 比如说给一个数 x=3  , 对x 各位取反(二进制)(x=~x ), 于是就是 1-0-0-1: 拿 1-0-0-1,从左到右(从高位到地位)顺序,来在字典树中寻找.如果能找到(if ),就接着找下去: 如果…

题目链接:Vasiliy's Multiset 题意:这里有一个set容器,有三种操作,+ num, - num, ? num,分别代表往容器里加上num,或者拿走num,或着从容器里找一个数temp使得temp^num的值最大.输出这个最大值. 思路:对于XOR操作,一般都要拆位考虑,拆完之后用Trie或者线段树维护,然后,这个题把每个数的二进制30位(前面不够的用0补全)插入Trie,查询的时候,对于每一位先尝试往相反的方向走,因为异或 只要越高位 相反值越大,然后再尝试往相同的方向走.最后…

题目链接: Hard problem 题意:每个字符串可以选择反转或者不反转,给出反转每个字符串的代价,问使最少的代价使得这个字符串序列成字典序. dp[i][j] = x : 第一维是第i个字符串,第二维表示当前字符串是否反转.x表示当前状态下使前i个字符串成字典序的最小代价. 感觉可以做的dp,然后我没写出来.T_T #include <stdio.h> #include <string.h> #include <iostream> #include <str…

A. Sereja and Algorithm 水题不解释. B. Sereja ans Anagrams 模p同余的为一组,随便搞. C. Sereja and the Arrangement of Numbers 我还以为是找规律... 把每个数当成一个点.就有一个图.让后求欧拉路什么的. D. Sereja and Sets 这个思路感觉很巧妙(可能是我太弱了),我们对于每一段连续的d,找到不包含它们的所有集合,这些集合的子集一定不可行. 见代码. /* * Problem: D. Ser…

Sereja and the Arrangement of Numbers 题解: ummm. 在一副图中,如果全部点的度数是偶数/只有2个点是奇数,则能一笔画. 考虑图的点数k为奇数的时候,那么每个点的度数都是偶数点,所以就是可以一笔画,答案为 1 +k * (i - kll) / 2; k为偶数的时候,所有的点是奇数点,我们保留2个点是奇数点,将其他的点改为偶数点,就可以一笔画了.  1 +k * (i - kll) / 2 + k/2 - 1. 代码: #include<bits/stdc…

Vasiliy's Multiset 题目链接: http://codeforces.com/contest/706/problem/D Description Author has gone out of the stories about Vasiliy, so here is just a formal task description. You are given q queries and a multiset A, initially containing only integer…

Hard problem 题目链接: http://codeforces.com/contest/706/problem/C Description Vasiliy is fond of solving different tasks. Today he found one he wasn't able to solve himself, so he asks you to help. Vasiliy is given n strings consisting of lowercase Engl…

Interesting drink 题目链接: http://codeforces.com/contest/706/problem/B Description Vasiliy likes to rest after a hard work, so you may often meet him in some bar nearby. As all programmers do, he loves the famous drink "Beecola", which can be bough…

Beru-taxi 题目链接: http://codeforces.com/contest/706/problem/A Description Vasiliy lives at point (a, b) of the coordinate plane. He is hurrying up to work so he wants to get out of his house as soon as possible. New app suggested n available Beru-taxi…

// trie树 Codeforces Round #367 D Vasiliy's Multiset // 题意:给一个集合,初始有0,+表示添加元素,-去除元素,?询问集合里面与x异或最大的值 // 思路:思路很好想,建立trie树,再贪心当前位是1则选0,0则选1 #include <bits/stdc++.h> using namespace std; #define LL long long const double inf = 123456789012345.0; const LL…