#include <stdio.h>
#include <string.h>


#define DIGIT (5)

int main()
{
	int i, j, n, temp;
	char num[2][DIGIT + 1];
	char ans[DIGIT + 2];
	char fmt[8];
	int len[2], index;
	
	// scanf format
	sprintf(fmt, "%%%ds", DIGIT);
	
	scanf("%d", &n);
	
	for (i = 0; i < n; ++i) {
		for (j = 0; j < 2; ++j) {
			scanf(fmt, num[j]);
			while (getchar() != '\n');
			
			len[j] = strlen(num[j]);
		}
		
		// bigger one
		index = (len[0] < len[1]) ? 1 : 0;
		
		ans[len[index] + 1] = '\0';
		
		temp = 0;
		for (j = 1; j <= len[index ^ 1]; ++j) {
			temp += (num[0][len[0] - j] - '0') + (num[1][len[1] - j] - '0');
			ans[len[index] - j + 1] = temp % 10 + '0';
			temp /= 10;
		}
		for (; j <= len[index]; ++j) {
			temp += (num[index][len[index] - j] - '0');
			ans[len[index] - j + 1] = temp % 10 + '0';
			temp /= 10;
		}
		
		if (temp) {
			if (len[index] == DIGIT) {
				puts("overflow");
			} else {
				ans[0] = '1';
				puts(ans);
			}
		} else {
			puts(ans + 1);
		}
	}
	
	return 0;
}