【22】Generate Parentheses

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:

[ "((()))", "(()())", "(())()", "()(())", "()()()" ]

简单DFS

void dfs(int cur,int n,vector<string> &res,string one,int left,int right){ if(cur == 2*n){ res.push_back(one); return; } if(left<n){ dfs(cur+1,n,res,one+"(",left+1,right); } if(right<n && left>right){ dfs(cur+1,n,res,one+")",left,right+1); } } vector<string> generateParenthesis(int n) { vector<string> res; dfs(0,n,res,"",0,0); return res; }