A - 栈

Description

 

You are given a string consisting of parentheses () and []. A string of this type is said to be correct:

(a)

if it is the empty string

(b)

if A and B are correct, AB is correct,

(c)

if A is correct,  (A  ) and  [A  ] is correct.

Write a program that takes a sequence of strings of this type and check their correctness. Your program can assume that the maximum string length is 128.

 

Input 

The file contains a positive integer  n and a sequence of  n strings of parentheses  () and  [], one string a line.

 

Output 

A sequence of  Yes or  No on the output file.

 

Sample Input 

 

3
([])
(([()])))
([()[]()])()

 

Sample Output 

Yes
No
Yes

 思路：

使用栈模拟就好

#include"iostream"
#include"cstring"
#include"stdio.h" using namespace std; int main() { int T; cin>>T; getchar(); while(T--) { char a[130]; gets(a); char stack[130]; int top=0; int len=strlen(a); bool ok=true; for(int i=0;i<len;i++) { if(a[i]=='('||a[i]=='[') { top++; stack[top]=a[i]; } if(a[i]==')') { if(stack[top]!='(') {ok=false; break; } top--; } if(a[i]==']') { if(stack[top]!='[') {ok=false; break; } top--; } } if(ok&&top==0) cout<<"Yes"<<endl; //必须判断栈是否为空，因为你必须保证左边的括号不会多了 else cout<<"No"<<endl; } return 0; }

 

转载于:https://www.cnblogs.com/zsyacm666666/p/4660443.html