A13588. LCM Problem
编程题
普及/提高-
知识点
题目描述
Let $LCM(x, y)$ 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 $l \le LCM(x, y) \le r$ .
You are given two integers $l$ and $r$ . Find two integers $x$ and $y$ such that $l \le x < y \le r$ and $l \le LCM(x, y) \le r$ .
输入格式
The 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 $r$ ( $1 \le l < r \le 10^9$ ).
Each test case is represented by one line containing two integers $l$ and $r$ ( $1 \le l < r \le 10^9$ ).
输出格式
For 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).
- 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).
输入输出样例
输入 #1
4 1 1337 13 69 2 4 88 89
输出 #1
6 7 14 21 2 4 -1 -1