#include <bits/stdc++.h> using namespace std; int main(){ string s,s1; cin>>s>>s1; int sum_s=0,sum_s1=0; for(int i=0;i<s.length();i++){ if(s[i]>='0'&&s[i]<='9') sum_s++; } for(int i=0;i<s1.length();i++){ if(s1[i]>='0'&&s1[i]<='9') sum_s1++; } if(sum_s>sum_s1){ for(int i=s1.length()-1;i>=0;i--){ cout<<s1[i]; } cout<<s[sum_s-1]; } else{ for(int i=s.length()-1;i>=0;i--){ cout<<s[i]; } cout<<s1[sum_s1-1]; } }