Leetcode 131：Palindrome Partitioning

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

Return all possible palindrome partitioning of s.

Example:

Input: “aab”
Output:
[
[“aa”,“b”],
[“a”,“a”,“b”]
]

C++
vector<vector<string>> partition(string s) {
        //将一个字符串拆分成回文串
        vector<vector<string>> res;
        vector<string> out;
        helper(s,0,out,res);
        return res;
    }
    void helper(string s,int start,vector<string>& out,vector<vector<string>>& res)
    {
        if(start == s.size())
        {
            res.push_back(out);
            return;
        }
        for(int i = start;i < s.size();++i)
        {
            if(!IsPalin(s,start,i))continue;
            out.push_back(s.substr(start,i-start+1));
            helper(s,i+1,out,res);
            out.pop_back();
        }
    }
    bool IsPalin(string s,int start,int end)
    {
        while(start <= end)
        {
            if(s[start] != s[end])
                return false;
            else
            {
                ++start;
                --end;
            }
        }
        return true;
    }