#include <iostream>
#include <string>
#include <algorithm>

int main(){
  std::string str1,str2,sumstr;
  while(std::cin>>str1>>str2){
    sumstr.clear();
    std::reverse(str1.begin(),str1.end());
    std::reverse(str2.begin(),str2.end());
    unsigned size=std::min(str1.size(),str2.size());
    unsigned i;
    unsigned carry=0;
    for(i=0;i<size;++i){
      unsigned sum=str1[i]+str2[i]+carry-'0'*2;
      sumstr.push_back(sum%10+'0');
      carry=sum/10;
    }
    std::string large=(str1.size()>str2.size())?str1:str2;
    for(;i<large.size();++i){
      unsigned sum=large[i]+carry-'0';
      sumstr.push_back(sum%10+'0');
      carry=sum/10;
    }
    if(carry)sumstr.push_back(carry+'0');
    std::reverse(sumstr.begin(),sumstr.end());
    sumstr.push_back('\0');
    if(sumstr.size()<=80)
      std::cout<<sumstr<<std::endl;
    else
      std::cout<<"overflow"<<std::endl;
  }
}