## Friday, December 21, 2012

### [LeetCode] Generate Parentheses 解题报告

Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.
For example, given n = 3, a solution set is:
`"((()))", "(()())", "(())()", "()(())", "()()()"`
» Solve this problem

[解题思路]

[Code]
``````1:  void CombinationPar(vector<string>& result, string& sample, int deep,
2:                           int n, int leftNum, int rightNum)
3:  {
4:       if(deep == 2*n)
5:       {
6:            result.push_back(sample);
7:            return;
8:       }
9:       if(leftNum<n)
10:       {
11:            sample.push_back('(');
12:            CombinationPar(result, sample, deep+1, n, leftNum+1, rightNum);
13:            sample.resize(sample.size()-1);
14:       }
15:       if(rightNum<leftNum)
16:       {
17:            sample.push_back(')');
18:            CombinationPar(result, sample, deep+1, n, leftNum, rightNum+1);
19:            sample.resize(sample.size()-1);
20:       }
21:  }
22:  vector<string> generateParenthesis(int n) {
23:       // Start typing your C/C++ solution below
24:       // DO NOT write int main() function
25:       vector<string> result;
26:       string sample;
27:       if(n!= 0)
28:            CombinationPar(result, sample, 0, n, 0, 0);
29:       return result;
30:  }
``````