#include<iostream>

#include<string>

#include<vector>

using namespace std;

void GenAnagram(vector<char> &Src, vector<char> &Dest,vector<char> &Order, vector<char> &Stack)

{

    if(!Src.empty())

    {

        Order.push_back('i');

        Stack.push_back(Src.back());

        Src.pop_back();

        GenAnagram(Src, Dest, Order, Stack);

        Src.push_back(Stack.back());

        Stack.pop_back();

        Order.pop_back();

    }

    if(!Stack.empty()&&Stack.back()==Dest[Stack.size() + Src.size() - ])

    {

        Order.push_back('o');

        char cTemp =Stack.back();

        Stack.pop_back();

        GenAnagram(Src, Dest, Order, Stack);

        Stack.push_back(cTemp);

        Order.pop_back();

    }
　　 //参考代码这块写错了

    if (Src.empty() && Stack.empty()) {

        vector<char>::iterator i = Order.begin();

        for (; i != Order.end(); ++i ) {

            cout << *i << ' ';

        }

         cout << endl;

    }

}

int main()

{

    for(string str1,str2;cin>>str1>>str2;cout<<']'<<endl)

    {

        cout<<'['<<endl;

        //反向输入

        vector<char> Src(str1.rbegin(), str1.rend());

        vector<char> Dest(str2.rbegin(), str2.rend());

        vector<char> Order, Stack;

        GenAnagram(Src, Dest, Order, Stack);

    }

    return ;

}