Bitwise exclusive OR (or bitwise addition modulo two) is a binary operation which is equivalent to applying logical exclusive OR to every pair of bits located on the same positions in binary notation of operands. In other words, a binary digit of the result is equal to 1 if and only if bits on the respective positions in the operands are different.

For example, if X=10910=11011012, Y=4110=1010012, then:
X xor Y=6810=10001002.
Write a program, which takes two non-negative integers A and B as an input and finds two non-negative integers X and Y, which satisfy the following conditions:
A=X+Y B=X xor Y, where xor is bitwise exclusive or. X is the smallest number among all numbers for which the first two conditions are true.

The first line contains integer number A and the second line contains integer number B (0 \le A,B \le 264-1).

The only output line should contain two integer non-negative numbers X and Y. Print the only number -1 if there is no answer.