A11782. Number Clicker
编程题
普及/提高-
知识点
题目描述
Allen is playing Number Clicker on his phone.
He starts with an integer $u$ on the screen. Every second, he can press one of 3 buttons.
1. Turn $u \to u+1 \pmod{p}$ .
2. Turn $u \to u+p-1 \pmod{p}$ .
3. Turn $u \to u^{p-2} \pmod{p}$ .
Allen wants to press at most 200 buttons and end up with $v$ on the screen. Help him!
He starts with an integer $u$ on the screen. Every second, he can press one of 3 buttons.
1. Turn $u \to u+1 \pmod{p}$ .
2. Turn $u \to u+p-1 \pmod{p}$ .
3. Turn $u \to u^{p-2} \pmod{p}$ .
Allen wants to press at most 200 buttons and end up with $v$ on the screen. Help him!
输入格式
The first line of the input contains 3 positive integers: $u, v, p$ ( $0 \le u, v \le p-1$ , $3 \le p \le 10^9 + 9$ ). $p$ is guaranteed to be prime.
输出格式
On the first line, print a single integer $\ell$ , the number of button presses. On the second line, print integers $c_1, \dots, c_\ell$ , the button presses. For $1 \le i \le \ell$ , $1 \le c_i \le 3$ .
We can show that the answer always exists.
We can show that the answer always exists.
输入输出样例
输入 #1
1 3 5
输出 #1
2 1 1
输入 #2
3 2 5
输出 #2
1 3
说明/提示
In the first example the integer on the screen changes as $1 \to 2 \to 3$ .
In the second example the integer on the screen changes as $3 \to 2$ .
In the second example the integer on the screen changes as $3 \to 2$ .