This version of the problem differs from the next one only in the constraint on $$$n$$$.
Note that the memory limit in this problem is lower than in others.
You have a vertical strip with $$$n$$$ cells, numbered consecutively from $$$1$$$ to $$$n$$$ from top to bottom.
You also have a token that is initially placed in cell $$$n$$$. You will move the token up until it arrives at cell $$$1$$$.
Let the token be in cell $$$x > 1$$$ at some moment. One shift of the token can have either of the following kinds:
Find the number of ways to move the token from cell $$$n$$$ to cell $$$1$$$ using one or more shifts, and print it modulo $$$m$$$. Note that if there are several ways to move the token from one cell to another in one shift, all these ways are considered distinct (check example explanation for a better understanding).
The only line contains two integers $$$n$$$ and $$$m$$$ ($$$2 \le n \le 2 \cdot 10^5$$$; $$$10^8 < m < 10^9$$$; $$$m$$$ is a prime number) — the length of the strip and the modulo.
Print the number of ways to move the token from cell $$$n$$$ to cell $$$1$$$, modulo $$$m$$$.
3 998244353
5
5 998244353
25
42 998244353
793019428
In the first test, there are three ways to move the token from cell $$$3$$$ to cell $$$1$$$ in one shift: using subtraction of $$$y = 2$$$, or using division by $$$z = 2$$$ or $$$z = 3$$$.
There are also two ways to move the token from cell $$$3$$$ to cell $$$1$$$ via cell $$$2$$$: first subtract $$$y = 1$$$, and then either subtract $$$y = 1$$$ again or divide by $$$z = 2$$$.
Therefore, there are five ways in total.
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