STL——括号匹配

Problem D: STL——括号匹配

Time Limit: 1 Sec  Memory Limit: 128 MB

Description

给出一堆括号，看其是否匹配，例如 ()、()()、(()) 这样的括号就匹配，)(、)()) 而这样的括号就不匹配

Input

每一行代表一组测试样例，每组测试样例只包含'('和')'，样例长度不超过100个字符

Output

如果所有的括号都匹配，那么输出YES，否则输出NO

Sample Input

()

)(

Sample Output

YES

NO

HINT

使用STL的stack容易实现。

 

1. #include<bits/stdc++.h>
2. using namespace std;
3. stack<char> bracket;
4. int main()
5. {
6.  
7.     char s[101];
8.     while(scanf("%s",s) == 1)
9.     {
10.         int num;
11.         num = strlen(s);
12.         while( bracket.size() )
13.             bracket.pop();
14.         int jump = 0;
15.         for(int i = 0; i < num; i++)
16.         {
17.             if(s[i] == '(')
18.             {
19.                 bracket.push(s[i]);
20.             }
21.             else if(s[i] == ')')
22.             {
23.                 if(bracket.empty())
24.                 {
25.                     cout<<"NO"<<endl;
26.                     jump++;
27.                     break;
28.                     //return 0;
29.                 }
30.                 else
31.                 {
32.                     bracket.top();
33.                     bracket.pop();
34.                 }
35.             }
36.         }
37.         if(!bracket.empty())
38.         {
39.             cout<<"NO"<<endl;
40.         }
41.         else
42.         {
43.             if(jump == 0)
44.             {
45.                 cout<<"YES"<<endl;
46.             }
47.  
48.         }
49.  
50.     }
51. }
52. /*
53. ())
54. )()()
55. ()
56. ((())
57.  */