Given non-zero two integers N and M. The problem is to find the number closest to N and divisible by M. If there are more than one such number, then output the one having maximum absolute value.
The first line consists of an integer T i.e number of test cases. T testcases follow. The first and only line of each test case contains two space separated integers N and M.
For each testcase, in a new line, print the closest number to N which is also divisible by M.
1 <= T <= 100
-1000 <= N, M <= 1000