#include<iostream>
#include<string>
#include<algorithm>
using namespace std;
int main(){
  string s,n,final;
  int o,c=0;
  cin>>s>>n;
  reverse(s.begin(),s.end());
  reverse(n.begin(),n.end());
  for(int i = 0; i < s.size() || i<n.size() || c;i++){
    o = (s.size() > i ? s[i]-'0' : 0) +(n.size() > i ? n[i]-'0' : 0) + c;

    //   o = (s[i]-'0')+(n[i]-'0')+c;
    c = o / 10;
    o %= 10;
    final.append(1,o+'0');
  }
  reverse(final.begin(),final.end());
  if(n.size()>=80 || s.size()>=80 || final.size()>=80) cout<<"overflow"<<endl;
  else cout<<final<<endl;
}