题目链接:http://codeforces.com/contest/670/problem/E 给你n长度的括号字符,m个操作,光标初始位置是p,'D'操作表示删除当前光标所在的字符对应的括号字符以内的所有字符(比如'(()())'),'R'操作表示右移光标,'L'操作表示左移光标.删除操作后光标向右移,要是再向右移没有字符的话,那就停在最后的字符上了.问你最后的括号字符是怎么样的. 这题用链表写简单多了,直接模拟操作就行了,我用stl里的list. #include <bits/stdc++…

E. Correct Bracket Sequence Editor 题目连接: http://www.codeforces.com/contest/670/problem/E Description Recently Polycarp started to develop a text editor that works only with correct bracket sequences (abbreviated as CBS). Note that a bracket sequence…

E. Correct Bracket Sequence Editor   Recently Polycarp started to develop a text editor that works only with correct bracket sequences (abbreviated as CBS). Note that a bracket sequence is correct if it is possible to get a correct mathematical expre…

题目链接: http://codeforces.com/contest/670/problem/E 题解: 用STL的list和stack模拟的,没想到跑的还挺快. 代码: #include<iostream> #include<cstdio> #include<cstring> #include<map> #include<list> #include<stack> using namespace std; + ; const in…

题目链接:https://codeforces.com/contest/670/problem/E 题意: 给出一个已经匹配的括号串,给出起始的光标位置(光标总是指向某个括号). 有如下操作: 1.往左移动一下光标: 2.往左移动一下光标: 3.删除当前光标指向的括号,以及和它匹配的那个括号,以及这两个括号之间的所有括号. 要求你给出在做完所有操作后的括号串. 题解: 数组模拟链表即可,每种操作都是 $O(1)$ 的时间复杂度. 另外可以参看:本题的对顶栈做法.本题的线段树做法. AC代码: #…

E. Correct Bracket Sequence Editor time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Recently Polycarp started to develop a text editor that works only with correct bracket sequences (abbrev…

time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output Recently Polycarp started to develop a text editor that works only with correct bracket sequences (abbreviated as CBS). Note that a bracket sequ…

Recently Polycarp started to develop a text editor that works only with correct bracket sequences (abbreviated as CBS). Note that a bracket sequence is correct if it is possible to get a correct mathematical expression by adding "+"-s and "…

F. Restore a Number   Vasya decided to pass a very large integer n to Kate. First, he wrote that number as a string, then he appended to the right integer k — the number of digits in n. Magically, all the numbers were shuffled in arbitrary order whil…

题目链接: http://codeforces.com/contest/670/problem/D2 题解: 二分答案. #include<iostream> #include<cstdio> #include<cstring> #include<map> using namespace std; + ; const int INF = 2e9; typedef __int64 LL; int n, k; int x[maxn], y[maxn]; bool…