class Solution{

public:

bool isScramble(string s1,string s2){

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

return false;

int len=s1.length();

if(len==0)

return true;

bool result=false;

for(int i=0;i<len;++i){

if(s2[i]==s1[0]){

result=isScramble(s1.substr(1,i),s2.substr(0,i))&&isScramble(s1.substr(i+1,len-i-1),s2.substr(i+1,len-i-1));

if(result)

return result;

}

}

return result;

}

};

your help is appreciated!