A. LCM Problemtime limit per test2 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard outputLet LCM(x, y) be the minimum positive integer that is divisible by both x and y. For example, LCM(13, 37) = 481, LCM(9, 6) = 18.You are given two integers l and r. Find two integers x and y such that l \le x < y \le r and l \le LCM(x, y) \le r.InputThe first line contains one integer t (1 \le t \le 10000) — the number of test cases.Each test case is represented by one line containing two integers l and r (1 \le l < r \le 10^9).OutputFor each test case, print two integers:  if it is impossible to find integers x and y meeting the constraints in the statement, print two integers equal to -1;  otherwise, print the values of x and y (if there are multiple valid answers, you may print any of them). ExampleInput
4
1 1337
13 69
2 4
88 89
Output
6 7
14 21
2 4
-1 -1

4
1 1337
13 69
2 4
88 89

6 7 14 21 2 4 -1 -1 
['constructive algorithms', 'greedy', 'math', 'number theory', '*800']