COCI '20 Contest 2 #3 Euklid

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Points: 17 (partial)
Time limit: 1.0s
Memory limit: 512M

Problem types

It is rarely mentioned that Euclid’s grandma was from Vrsi in Croatia. It is from there that Euclid’s less known (but equally talented in his youth) cousin Edicul∗ comes from.

It happened one day that they were playing “invent an algorithm”. Edicul writes two positive integers on the sand. Then he does the following: while neither number on the sand is 1, he marks them as (a, b) so that a \ge b. Then the numbers are erased and he writes (\lfloor{\frac{a}{b}}\rfloor, b) on the sand, and repeats the process. When one of the two numbers becomes 1, the other is the results of his algorithm.

Formally, if a and b are positive integers, the result R(a, b) of Edicul's algorithm is: \displaystyle  R(a,b)=   \left\{
\begin{array}{ll}
      R(b,a) & \text{if } a < b \\
      R~(\lfloor{\frac{a}{b}}\rfloor, b) & \text{if } a \ge b > 1 \\
      a & \text{if } a \ge b = 1 \\
\end{array} 
\right.

Euclid thinks for a while, and says: "Edicul, I have a better idea...", and the rest is history. Unfortunately, Edicul never became famous for his idea in number theory. This sad story inspires the following problem:

Given positive integers g and h, find positive integers a and b such that their greatest common divisor is g, and the result of Edicul's algorithm R(a, b) is h.

Input

The first line contains a single integer t (1 \le t \le 40) – the number of independent test cases.

Each of the following t lines contains two positive integers g_i and h_i (h_i \ge 2).

Output

Output t lines in total. For the i-th testcase, output positive integers a_i and b_i such that gcd(a_i
, b_i) = g_i and R(a_i
, b_i) = h_i.

The numbers in the output must not be larger than 10^{18}. It can be proven that for the given constraints, a solution always exists.

If there are multiple solutions for some testcase, output any of them.

Scoring

In all subtasks, 1 \le g \le 200\,000 and 2 \le h \le 200\,000.

Subtask Score Constraints
1 4 g=h
2 8 h=2
3 8 g=h^2
4 15 g,h \le 20
5 40 g,h \le 2\,000
6 35 No additional constraints.

Sample Input 1

1
1 4

Sample Output 1

99 23

Explanation for Sample Output 1

The integers 99 and 23 are coprime, i.e. their greatest common divisor is 1. We have \lfloor{\frac{99}{23}}\rfloor = 4, thus R(99, 23) = R(4, 23) = R(23, 4). Then \lfloor{\frac{23}{4}}\rfloor = 5, so R(23, 4) = R(5, 4) = R(1, 4) = R(4, 1) = 4.

Sample Input 2

2
3 2
5 5

Sample Output 2

9 39
5 5

Explanation for Sample Output 2

For the first testcase, gcd(9, 39) = 3 and R(9, 39) = 2.

For the second testcase, gcd(5, 5) = 5 and R(5, 5) = 5.


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