Dazzler has a task for you.

Given two positive integers A and B, find two positive integers i and j such that:

gcd > 1;
A ≤ i < j ≤ B;
The value (i + j) is minimum possible.

If there are multiple solutions, you may print any of them. If no such pair exists, print -1.

------ Input Format ------

• First line will contain T, number of test cases. Then the test cases follow.
• Each test case contains of a single line of input, two integers A and B.

------ Output Format ------

For each test case, output in a single line two space-separated integers i and j satisfying all the conditions. If no such pair exists, print -1.

------ Constraints ------

$1 ≤ T ≤ 10^{5}$
$1 ≤ A < B ≤ 10^{9}$

----- Sample Input 1 ------
2
2 3
2 10

----- Sample Output 1 ------
-1
2 4

----- explanation 1 ------
Test case $1$: There exists no pair satisfying all the conditions.

Test case $2$: A valid pair satisfying all the conditions is $(i, j) = (2, 4)$. The value $\texttt{gcd}(2, 4) = 2 >1$. The value $(i+j) = 6$.
It can be proven that no such pair exists that satisfies all the conditions and has sum less than $6$.

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