判断字符串中的括号是否成对出现

 1 #include <iostream>
 2 #include <stack>
 3 using namespace std;
 4 
 5 int _tmain(int argc, _TCHAR* argv[])
 6 {
 7     string sss = "((1+(2+3))+6))";
 8     stack<char> st;
 9     bool bFlag = true;
10     for (auto ch : sss)
11     {
12         if (ch == ‘(‘)
13         {
14             st.push(ch);
15         }
16         else
17         {
18             if (ch == ‘)‘)
19             {
20                 if (st.empty())
21                 {
22                     bFlag = false;
23                     break;
24                 }
25                 else
26                 {
27                     st.pop();
28                 }
29             }
30         }
31     }
32     if (st.empty() && bFlag)
33     {
34         cout << "pipei" << endl;
35     }
36     else
37     {
38         cout << "bu pipei" << endl;
39     }
40 
41     system("PAUSE");
42     return 0;
43 }