Problem9323--ABC297 —— Ex - Diff Adjacent

9323: ABC297 —— Ex - Diff Adjacent

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

A positive-integer sequence is said to be splendid if no two adjacent elements are equal.

Find the sum, modulo $998244353$, of the lengths of all splendid sequences whose elements have a sum of $N$.

Input

The input is given from Standard Input in the following format:

```
$N$
```

Output

Print the answer.

Constraints

$1 \le N \le 2 \times 10^5$
All values in the input are integers.

Sample 1 Input

4

Sample 1 Output

8
There are four splendid sequences whose sum is 4: (4),(1,3),(3,1),(1,2,1). Thus, the answer is the sum of their lengths: 1+2+2+3=8.
(2,2) and (1,1,2) also have a sum of 4 but ineligible because their 1-st and 2-nd elements are the same.

Sample 2 Input

297

Sample 2 Output

475867236

Sample 3 Input

123456

Sample 3 Output

771773807

Source/Category