#include <iostream>
#include <string>
using namespace std;
string reverse(string::iterator& it)
{
char head=*it;
++it;
if(head=='b' || head=='w')
return string(1,head);
string upperLeft=reverse(it);
string upperRight=reverse(it);
string lowerLeft=reverse(it);
string lowerRight=reverse(it);
return string("x")+lowerLeft+lowerRight+upperLeft+upperRight;
}
int main() {
string s="xwwwb";
string::iterator it=s.begin();
it++;
cout<<string(1,*it);
}
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