#include<iostream>
#include<string.h>
#define MAX(x,y) (x>y?x:y)
using namespace std;

int N;
int sum[1000][100];
	char stra[1000][85],strb[1000][85];

int main(){
	int i,j;
	int a[100],b[100];
	cin >> N;
	for(i = 0;i < N;i++){
		for(j = 0;j < 100;j++){
			a[j] = 0;
			b[j] = 0;
		}
		cin >> stra[i];
		for(j = strlen(stra[i])-1;j >= 0;j--){
			a[j] = stra[i][strlen(stra[i])-1-j]-48;
		}
		cin >> strb[i];
		for(j = strlen(strb[i])-1;j >= 0;j--){
			b[j] = strb[i][strlen(strb[i])-1-j]-48;
		}
		for(j = 0;j < MAX(strlen(stra[i]),strlen(strb[i]));j++){
			sum[i][j] += (a[j]+b[j]);
			sum[i][j+1] += (sum[i][j])/10;
			sum[i][j] %= 10;
		}
	}
	for(i = 0;i < N;i++){
		for(j = 99;sum[i][j] == 0 && j > 0;j--);
		if(j >= 80)
			cout << "overflow" << endl;
		else{
			for(j;j >= 0;j--)
				cout << sum[i][j];
			cout << endl;
		}
	}
	return 0;
}