Background

Zhang Hua was admitted to Peking University; Li Ping entered a secondary technical school; Little E is moving bricks at a construction site: they all have a bright future.

Because moving bricks is too tiring, Little E decides to work in a factory tightening screws. However, Little E meets a boss who always tries to make things difficult.

Problem Description

To produce one module, $n$ screws must be tightened. However, every $10$ minutes, Little E's boss will come to Little E's workstation and take away one unfinished module. During each such period, Little E only has enough time to tighten $k$ screws.

Little E's boss has just left. Ask: on which upcoming visit (the $x$-th time) is it possible for Little E to have a finished module? Assume Little E's boss tries as hard as possible to prevent Little E from achieving this.

Input Format

One line with two positive integers, $n,k$.

Output Format

If Little E can never have a finished module no matter what, output one line Poor E.S.!.

Otherwise output one line with one positive integer, the answer.

3 2

2

Hint

Sample Explanation 1

Little E first chooses two modules and tightens one screw on each of them. Then the boss comes and takes away one. Next, Little E only needs to tighten two more screws on the remaining module to finish it. So when the boss comes the second time, Little E already has one finished module. Note that when the boss comes, Little E cannot have a module with screws only half-tightened; otherwise, the boss will see it and say Little E's work is unqualified.

Subtasks

It is guaranteed that $1\le k \le n \le 10^5$.

Source

From the preliminary round of the 2023 Tsinghua University Student Algorithmic Contest and Intercollegiate Invitational (THUPC2023).

Resources such as solutions can be found at https://github.com/THUSAAC/THUPC2023-Pre.

Translated by ChatGPT 5