#include<iostream>
#include<algorithm>
#include<cstring>
#include<string>
#include<cstdio>
#define MOJI 48
using namespace std;
int multiple(string a,string b);
char c[111111];
int main(){
  int n;
  string a,b;
  while(cin >> n){
    for(int i=0;i<n;i++){
      cin >> a;
      cin >> b;
      int k = multiple( a , b );
      if(k>=80){
	cout << "overflow" << endl;
      }else {
	for(int i=k-1;i>=0;i--){
	  printf("%d",c[i]);
	}
	cout << endl;
      }
    }
  }
}
int multiple(string a,string b){
  int a_size,b_size,w=0;
  char k = 0; // 桁上げ
  a_size = a.size();
  b_size = b.size();
  while(a_size>0 || b_size>0 || k == 1){
    if(a_size>0 && b_size>0){
      c[w] = (a[a_size-1] - MOJI + b[b_size-1] - MOJI + k) % 10;
      k = (k + (a[a_size-1]-MOJI) + (b[b_size-1]-MOJI)) / 10;
    }
    else if(a_size>0 && b_size<=0){
      c[w] = ((a[a_size-1]-MOJI) + k) % 10;
      k = (a[a_size-1]-MOJI + k) / 10;
    }
    else if(a_size<=0 && b_size>0){
      c[w] = (b[b_size-1] - MOJI + k) % 10;
      k = (k + b[b_size-1] - MOJI) / 10;
    }else {
      c[w] = k;
      k = 0;
    }
    a_size--;
    b_size--;
    w++;
  }
  return w;
}