Add Backward Numbers

A backward number is written in ordinary Arabic numerals, but with the order of its digits reversed: the first digit becomes the last, and vice versa. For example, the number $1245$ becomes $5421$.

All leading zeroes are omitted. So if a number ends in a zero, that zero is lost by the reversal; for example, $1200$ becomes $21$. Consequently, a backward number never has any trailing zeroes.

Your task is to add two backward numbers and output their sum, again as a backward number. In general the result is not unique (for example, $21$ could have come from $12$, $120$, or $1200$), so we assume that no zeroes were lost in the reversal (that is, we assume the original number was $12$).

The first line contains a single integer $N$ ($N > 0$), the number of cases. Each of the following $N$ lines contains two non-negative integers separated by a space; these are the backward numbers to add. Every number satisfies $0 \le n < 10^9$.

For each case, print exactly one line containing a single integer: the backward sum of the two backward numbers. Omit any leading zeroes.