B. Moderate Modular Modetime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard outputYouKn0wWho has two even integers x and y. Help him to find an integer n such that 1 \le n \le 2 \cdot 10^{18} and n \bmod x = y \bmod n. Here, a \bmod b denotes the remainder of a after division by b. If there are multiple such integers, output any. It can be shown that such an integer always exists under the given constraints.InputThe first line contains a single integer t (1 \le t \le 10^5)  — the number of test cases.The first and only line of each test case contains two integers x and y (2 \le x, y \le 10^9, both are even).OutputFor each test case, print a single integer n (1 \le n \le 2 \cdot 10^{18}) that satisfies the condition mentioned in the statement. If there are multiple such integers, output any. It can be shown that such an integer always exists under the given constraints.ExampleInput
4
4 8
4 2
420 420
69420 42068
Output
4
10
420
9969128
NoteIn the first test case, 4 \bmod 4 = 8 \bmod 4 = 0.In the second test case, 10 \bmod 4 = 2 \bmod 10 = 2.In the third test case, 420 \bmod 420 = 420 \bmod 420 = 0.
4
4 8
4 2
420 420
69420 42068

4 10 420 9969128 
['constructive algorithms', 'math', 'number theory', '*1600']