## Problem A: Beat the Spread!

Superbowl Sunday is nearly here. In order to pass the time waiting for
the half-time commercials and wardrobe malfunctions, the local hackers
have organized a betting pool on the game. Members place their bets on
the sum of the two final scores, or on the absolute difference between the
two scores.
Given the winning numbers for each type of bet, can you deduce the final
scores?

The first line of input contains *n*, the number of test cases.
*n* lines follow, each representing a test case. Each test case
gives *s* and *d*, non-negative integers representing
the sum and (absolute) difference between
the two final scores. For each test case, output a line giving
the two final scores, largest first. If there are no such scores,
output a line containing "impossible". Recall that football scores
are always non-negative integers.

### Sample Input

2
40 20
20 40

### Output for Sample Input

30 10
impossible

*Gordon V. Cormack*