class Solution {

public:

    bool isScramble(string s1, string s2) {

        if(s1.size() != s2.size())

            return false;

        if(s1.size() ==  || s1 == s2)

            return true;

        string sa = s1;

        string sb = s2;

        sort(sa.begin(),sa.end());

        sort(sb.begin(),sb.end());

        if(sa != sb)

            return false;

        for(int i = ; i < s1.size(); i++)

        {

            string s11 = s1.substr(,i);

            string s12 = s1.substr(i,s1.size() - i);

            string s21 = s2.substr(,i);

            string s22 = s2.substr(i,s2.size() - i);

            string s31 = s2.substr(,s2.size() - i);

            string s32 = s2.substr(s2.size() - i,s2.size());

            if(isScramble(s11,s21)&&isScramble(s12,s22) || isScramble(s11,s32)&&isScramble(s12,s31))

                return true;

        }

        return false;

    }

};