题目描述
Problem Statement
There is a grid with $1 \times N squares, numbered 1,2,\dots,N$ from left to right.
Takahashi prepared paints of C colors and painted each square in one of the C colors.
Then, there were at most two colors in any consecutive K squares.
Formally, for every integer i such that $1 \le i \le N-K+1,$ there were at most two colors in squares $i,i+1,\dots,i+K-1$.
In how many ways could Takahashi paint the squares?
Since this number can be enormous, find it modulo 998244353.
Input
The input is given from Standard Input in the following format:
N K C
Output
Print the answer as an integer.
Constraints
- All values in the input are integers.
- $2 \le K \le N \le 10^6$
- $1 \le C \le 10^9$
Sample Input 1
3 3 3
Sample Output 1
21
In this input, we have $a 1 \times 3$ grid.
Among the 27 ways to paint the squares, there are 6 ways to paint all squares in different colors, and the remaining 21 ways are such that there are at most two colors in any consecutive three squares.
Sample Input 2
10 5 2
Sample Output 2
1024
Since C=2, no matter how the squares are painted, there are at most two colors in any consecutive K squares.
Sample Input 3
998 244 353
Sample Output 3
952364159
Print the number modulo 998244353.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分