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A14430. Gregor and Cryptography

编程题 普及/提高-

题目描述

Gregor is learning about RSA cryptography, and although he doesn't understand how RSA works, he is now fascinated with prime numbers and factoring them.

Gregor's favorite prime number is $P$ . Gregor wants to find two bases of $P$ . Formally, Gregor is looking for two integers $a$ and $b$ which satisfy both of the following properties.

- $P \bmod a = P \bmod b$ , where $x \bmod y$ denotes the remainder when $x$ is divided by $y$ , and
- $2 \le a < b \le P$ .

Help Gregor find two bases of his favorite prime number!

输入格式

Each test contains multiple test cases. The first line contains the number of test cases $t$ ( $1 \le t \le 1000$ ).

Each subsequent line contains the integer $P$ ( $5 \le P \le {10}^9$ ), with $P$ guaranteed to be prime.

输出格式

Your output should consist of $t$ lines. Each line should consist of two integers $a$ and $b$ ( $2 \le a < b \le P$ ). If there are multiple possible solutions, print any.

输入输出样例

输入 #1
2
17
5
输出 #1
3 5
2 4

说明/提示

The first query is $P=17$ . $a=3$ and $b=5$ are valid bases in this case, because $17 \bmod 3 = 17 \bmod 5 = 2$ . There are other pairs which work as well.

In the second query, with $P=5$ , the only solution is $a=2$ and $b=4$ .
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