题目描述
Problem Background
Ysuperman particularly enjoys playing with numbers.
Originally, this problem was intended to be named "亦旧亦久罢以龄" (Eternal and Timeless), but since other problem titles are only two characters long, a longer name wouldn't be suitable.
Problem Description
During his leisure time, Ysuperman chooses to pass the time using a calculator. He inputs a very long decimal number $S$. Specifically, $S$ has $n$ digits. For clarity, let the digit at the $i$-th position from the least significant digit be $S_i$ (with indexing starting from 1).
Ysuperman will select a non-zero digit to perform a "rounding" operation. Specifically, if the $i$-th digit is chosen for rounding:
- If $S_i < 5$, then subtract $S_i \cdot 10^{i-1}$ from $S$.
- If $S_i \geq 5$, then add $10^i$ to $S$ and then subtract $S_i \cdot 10^{i-1}$.
After several operations, $S$ will eventually become zero. The question is, how many different ways are there to reduce $S$ to zero? Two methods are considered different if and only if the position of the operation chosen differs at some step.
Input Format
A high-precision number $S$.
Output Format
The number of different ways to reduce $S$ to zero, modulo $998244353$.
Sample Input and Output
Sample Input #1
5
Sample Output #1
1
Sample Input #2
45
Sample Output #2
2
Sample Input #3
55
Sample Output #3
4
Sample Input #4
3333
Sample Output #4
24
Sample Input #5
999999
Sample Output #5
16336
Sample Input #6
1919810
Sample Output #6
3461
Sample Input #7
11451419
Sample Output #7
210000
Notes
Sample Explanation
Sample Explanation #1
$\underline{5} \to \underline{1}0 \to 0$
There is 1 way.
Sample Explanation #2
$\underline{4}5 \to \underline{5} \to \underline{1}0 \to 0$
$4\underline{5} \to \underline{5}0 \to \underline{1}00 \to 0$
There are 2 ways.
Sample Explanation #3
$\underline{5}5 \to \underline{1}05 \to \underline{5} \to \underline{1}0 \to 0$
$\underline{5}5 \to 10\underline{5} \to \underline{1}10 \to \underline{1}0 \to 0$
$\underline{5}5 \to 10\underline{5} \to 1\underline{1}0 \to \underline{1}00 \to 0$
$5\underline{5} \to \underline{6}0 \to \underline{1}00 \to 0$
There are 4 ways.
Data Range
This problem uses batched testing.
| Subtask | $n$ | $S_i \in$ | Score |
|---|---|---|---|
| 0 | $\leq 6$ | $[0, 9]$ | 5 |
| 1 | $\leq 15$ | $[0, 9]$ | 13 |
| 2 | $\leq 40$ | $[0, 4]$ | 5 |
| 3 | $\leq 40$ | $\{9\}$ | 12 |
| 4 | $\leq 40$ | $[5, 8]$ | 15 |
| 5 | $\leq 40$ | $[0, 9]$ | 30 |
| 6 | $\leq 64$ | $[0, 9]$ | 20 |
For $100\%$ of the data, $1 \leq n \leq 64$ and $S$ does not have leading zeros.
Hints
The time limit for this problem is $1145ms$.
The problem is not difficult.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分