#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ char a[1001]={},b[1001]={}; cin>>a>>b; int la=strlen(a),lb=strlen(b),a1=0,b1=0; for(int i=0;i<la;i++){ if('0'<=a[i]&&a[i]<='9')a1++; } for(int j=0;j<lb;j++){ if('0'<=b[j]&&b[j]<='9')b1++; } if(a1>b1){ for(int i=lb-1;i>=0;i--)cout<<b[i]; cout<<a[a1-1]<<endl; } else{ for(int i=la-1;i>=0;i--)cout<<a[i]; cout<<b[b1-1]<<endl; } return 0; }