Given a string s, partition s such that every substring of the partition is a palindrome.

Return all possible palindrome partitioning of s.

For example, given s = "aab",
Return

  [
    ["aa","b"],
    ["a","a","b"]
  ]

class Solution {
public:
    std::vector<std::vector<std::string>> partition(std::string s) {
		std::vector<std::vector<std::string>> result;
		std::vector<std::string> ans;
		dfs(s,ans,result);
#if 0
		for (int i = 0; i < result.size(); i++)
		{
			for (int j = 0; j < result[i].size(); j++)
			{
				std::cout << result[i][j] << " ";
			}
			std::cout << std::endl;
		}
#endif // 1

		return result;
    }
private:
	void dfs(std::string s,std::vector<std::string> &ans,std::vector<std::vector<std::string>> &result)
	{
		if(s.size() < 1)
		{
			result.push_back(ans);
			return ;
		}
		for (int i = 0; i < s.size(); i++)
		{
			int a = 0,b = i;
			while(a < b)
			{
				if(s[a] == s[b]) a++,b--;
				else break;
			}
			if(a >= b)
			{
				ans.push_back(s.substr(0,i+1));
				dfs(s.substr(i+1),ans,result);
				ans.pop_back();
			}
		}
	}
};

leetcode - Palindrome Partitioning