Mid semesters are nearly here. In order to pass the time waiting for the question paper malfunctions, the students have organized a betting pool on students that will pass the semester and the students that will fail.
Students place their bets on the sum of the students that will pass and students that will fail, or on the absolute difference between the students that will pass and students that will fail.
Given the winning numbers for each type of bet, can you deduce the final counts?
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 counts.
For each test case, output a line giving the two final counts, largest first. If there are no such counts possible, output a line containing “impossible”. Recall that the count (number of students) are always non-negative integers.
Do not worry about the constraints.
