<p>Given a string <code>s</code>, partition <code>s</code> such that every <span data-keyword="substring-nonempty">substring</span> of the partition is a <span data-keyword="palindrome-string"><strong>palindrome</strong></span>. Return <em>all possible palindrome partitioning of </em><code>s</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> s = "aab"
<strong>Output:</strong> [["a","a","b"],["aa","b"]]
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> s = "a"
<strong>Output:</strong> [["a"]]
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= s.length &lt;= 16</code></li>
	<li><code>s</code> contains only lowercase English letters.</li>
</ul>

class Solution {
public:
    vector<vector<string>> ans;

    bool palindrome(const std::string& s, int i, int j) 
    {
    while (i < j) {
        if (s[i] != s[j]) {
            return false;
        }
        i++;
        j--;
    }
        return true;
    }

    string substr(string s, int i, int j)
    {
        string f="";
        for(int k=i;k<=j;k++)
        {
            f=f+s[k];
        }
        return f;
    }

    void helper(string s, int low, vector<string> tmp)
    {

        if(low>=s.size()){ ans.push_back(tmp); return;}
        
        for(int i=low;i<s.size();i++)
        {       
            if(palindrome(s,low,i))
            {
                string sub= substr(s,low,i);
                tmp.push_back(sub);
                helper(s,i+1,tmp);
                tmp.pop_back();
            }

        }
    }

    vector<vector<string>> partition(string s) 
    {
        int low=0;
        vector<string> tmp;
        helper(s,low,tmp);
        return ans;
    }
};
177556