CF思维联系– Codeforces-990C Bracket Sequences Concatenation Problem(括号匹配+模拟)
ACM思维题训练集合
A bracket sequence is a string containing only characters “(” and “)”.
A regular bracket sequence is a bracket sequence that can be transformed into a correct arithmetic expression by inserting characters “1” and “+” between the original characters of the sequence. For example, bracket sequences “()()”, “(())” are regular (the resulting expressions are: “(1)+(1)”, “((1+1)+1)”), and “)(” and “(” are not.
You are given n bracket sequences s1,s2,…,sn. Calculate the number of pairs i,j(1≤i,j≤n) such that the bracket sequence si+sj is a regular bracket sequence. Operation + means concatenation i.e. “()(” + “)()” = “()()()”.
If si+sj and sj+si are regular bracket sequences and i≠j, then both pairs (i,j) and (j,i) must be counted in the answer. Also, if si+si is a regular bracket sequence, the pair (i,i) must be counted in the answer.
Input
The first line contains one integer n(1≤n≤3⋅105) — the number of bracket sequences. The following n lines contain bracket sequences — non-empty strings consisting only of characters “(” and “)”. The sum of lengths of all bracket sequences does not exceed 3⋅105.
Output
In the single line print a single integer — the number of pairs i,j(1≤i,j≤n) such that the bracket sequence si+sj is a regular bracket sequence.
Examples
Input
3
)
()
(
Output
2
Input
2
()
()
Output
4
Note
In the first example, suitable pairs are (3,1) and (2,2).
In the second example, any pair is suitable, namely (1,1),(1,2),(2,1),(2,2).
模拟稍微有一下就可以了
#include <bits/stdc++.h>
using namespace std;
template <typename t>
void read(t &x)
{
char ch = getchar();
x = 0;
t f = 1;
while (ch < '0' || ch > '9')
f = (ch == '-' ? -1 : f), ch = getchar();
while (ch >= '0' && ch <= '9')
x = x * 10 + ch - '0', ch = getchar();
x *= f;
}
#define wi(n) printf("%d ", n)
#define wl(n) printf("%lld ", n)
#define rep(m, n, i) for (int i = m; i < n; ++i)
#define rrep(m, n, i) for (int i = m; i > n; --i)
#define P puts(" ")
typedef long long ll;
#define MOD 1000000007
#define mp(a, b) make_pair(a, b)
#define N 1005
#define fil(a, n) rep(0, n, i) read(a[i])
//---------------https://lunatic.blog.csdn.net/-------------------//
map<LL, LL> mp;
char con[N];
int main()
{
LL i, p, j, n, check;
LL cont = 0, ans = 0, len1, len2;
scanf("%lld", &n);
getchar();
for (j = 1; j <= n; j++)
{
p = check = 0;
len1 = len2 = 0;
memset(con, 0, sizeof(0));
scanf("%s", con);
for (i = 0; i < 300009; i++)
{
if (con[i] == 0)
break;
if (con[i] == '(')
{
len1++;
p++;
}
else
{
p--;
if (len1)
len1--;
else
len2++;
}
}
if (len1 == 0 && len2 == 0)
cont++;
else
{
if (len1 == 0)
mp[p]++;
if (len2 == 0)
mp[p]++;
}
}
ans = cont * cont;
map<LL, LL>::iterator it1;
for (it1 = mp.begin(); it1 != mp.end(); it1++)
{
if (it1->first > 0)
break;
if (mp[-(it1->first)] > 0)
ans += (it1->second) * mp[-(it1->first)];
}
printf("%lld\n", ans);
return 0;
}
CF思维联系– Codeforces-990C Bracket Sequences Concatenation Problem(括号匹配+模拟)的更多相关文章
- Bracket Sequences Concatenation Problem括号序列拼接问题(栈+map+思维)
A bracket(括号) sequence is a string containing only characters "(" and ")".A regu ...
- CF 990C. Bracket Sequences Concatenation Problem【栈/括号匹配】
[链接]:CF [题意]: 给出n个字符串,保证只包含'('和')',求从中取2个字符串链接后形成正确的括号序列的方案数(每个串都可以重复使用)(像'()()'和'(())'这样的都是合法的,像')( ...
- CF990C Bracket Sequences Concatenation Problem 思维 第五道 括号经典处理题目
Bracket Sequences Concatenation Problem time limit per test 2 seconds memory limit per test 256 meg ...
- CF思维联系–CodeForces -224C - Bracket Sequence
ACM思维题训练集合 A bracket sequence is a string, containing only characters "(", ")", ...
- Bracket Sequences Concatenation Problem CodeForces - 990C(括号匹配水题)
明确一下 一个字符串有x左括号不匹配 和 另一个字符串有x个右括号不匹配 这俩是一定能够匹配的 脑子有点迷 emm... 所以统计就好了 统计x个左括号的有几个,x个右括号的有几个 然后 乘一 ...
- CF思维联系--CodeForces - 218C E - Ice Skating (并查集)
题目地址:24道CF的DIv2 CD题有兴趣可以做一下. ACM思维题训练集合 Bajtek is learning to skate on ice. He's a beginner, so his ...
- CF思维联系– CodeForces - 991C Candies(二分)
ACM思维题训练集合 After passing a test, Vasya got himself a box of n candies. He decided to eat an equal am ...
- CF思维联系–CodeForces - 225C. Barcode(二路动态规划)
ACM思维题训练集合 Desciption You've got an n × m pixel picture. Each pixel can be white or black. Your task ...
- CF思维联系–CodeForces - 223 C Partial Sums(组合数学的先线性递推)
ACM思维题训练集合 You've got an array a, consisting of n integers. The array elements are indexed from 1 to ...
随机推荐
- ssh秘钥免交互批量分发脚本
将以下内容保存为.sh文件后运行即可,需根据各自情况修改ip_up和ip_arr #!/bin/bash #脚本功能:ssh秘钥免交互批量分发 #制 作 人:罗钢 联系方式:278554547@qqc ...
- 登录窗口java
这次代码是登录窗口的制作. 主要的方面是是包括,用户名.密码.验证码.以及输入数据所需要的文本框,对于验证码可以通过点击验证码进行修改.同时对于验证码的前景色和背景色同时都得到修改. 点击注册(这里还 ...
- MAC中PHP7.3安装mysql扩展
1.下载mysql扩展http://git.php.net/?p=pecl/database/mysql.git;a=summary 2.解压tar xzvf mysql-d7643af.tar.gz ...
- Django模拟ASP.NET MVC 自动匹配路由(转载)
项目结构 操作步骤 1.创建项目结构如上图 2.在myapp目录下创建urls文件,代码: from django.conf.urls import patterns, url from untitl ...
- virtual box设置网络,使用nat网络和仅主机(Host Only)网络进行连接
virtual box设置网络,使用nat网络和仅主机(Host Only)网络进行连接 前言 作为程序员难免要在本机电脑安装虚拟机,最近在用virtual box安装虚拟机的时候遇到了点问题. 对于 ...
- 测量C++程序运行时间
有个很奇怪的现象,我自认为写得好的文章阅读量只有一百多,随手写的却有一千多--要么是胡搞,要么是比较浅显.纵观博客园里众多阅读过万的文章,若非绝世之作,则必为介绍入门级知识的短文.为了让我的十八线博客 ...
- 在linux中使用mailx发送邮件
[root@ml ~]# yum -y install mailx #安装 [root@ml ~]# vim /etc/mail.rc 在最后一行添加(我这里使用的是qq邮箱): @qq.com ...
- java接口工厂模式理解
作为实际java开发经验还不到一年的我,第一次写博客,诚惶诚恐,怕把自己的谬误公之于众,误人子弟,不过转念一想,若是能有同行加以指点评判,将他们的真知灼见描述出来,那这篇文章就算抛转引玉了. 最近在阅 ...
- 使用snapjs实现svg路径描边动画
一,snap.svg插件在近几天,突然接到一个需求,内容是要在网页上写一个路径的动画,还需要可以随意控制动画的速度,开始于结束,本来是一个图片可以解决的问题,结果就这样变难了呀,在网上查一会之后,突然 ...
- d3.js v4曲线图的拖拽功能实现Zoom
zoom缩放案例 源码:https://github.com/HK-Kevin/d...:demo:https://hk-kevin.github.io/d3...: 原理:通过zoom事件来重新绘制 ...