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.

 

The file contains a positive integer 

n

 and a sequence of 

n

 strings of parentheses 

()

 and 

[]

, one string a line.

 

A sequence of 

Yes

 or 

No

 on the output file.

 

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

 

YesNoYes

水题一道，用stack

#include 
    
     #include 
     
      #include 
      
       #include 
       
        using namespace std;bool is_ok(char x, char y){	if (x == '(') return y == ')';	if (x == '[') return y == ']';	return false;}int main(){	int T; cin >> T;	cin.get();	while (T--)	{		string str; getline(cin, str);		stack
        
          all;		for (size_t i = 0; i < str.length(); i++){			char t = str[i];			if (all.empty() || !is_ok(all.top(), t))				all.push(t);			else				all.pop();		}		if (all.empty())			cout << "Yes" << endl;		else			cout << "No" << endl;	}	return 0;}