Problem:
Score : 500 points

Problem Statement

There are N blocks arranged in a row. Let us paint these blocks.

We will consider two ways to paint the blocks different if and only if there is a block painted in different colors in those two ways.

Find the number of ways to paint the blocks under the following conditions:

For each block, use one of the M colors, Color 1 through Color M, to paint it. It is not mandatory to use all the colors.

There may be at most K pairs of adjacent blocks that are painted in the same color.

Since the count may be enormous, print it modulo 998244353.

Constraints

All values in input are integers.

1 \leq N, M \leq 2 \times 10^5

0 \leq K \leq N - 1

Input

Input is given from Standard Input in the following format:

N M K

Output

Print the answer.

Sample Input 1

3 2 1

Sample Output 1

6

The following ways to paint the blocks satisfy the conditions: 112, 121, 122, 211, 212, and 221. Here, digits represent the colors of the blocks.

Sample Input 2

100 100 0

Sample Output 2

73074801

Sample Input 3

60522 114575 7559

Sample Output 3

479519525

Solution in PyPy3 (7.3.0) (judge verdict: Accepted)

from collections import defaultdict
mod = 998244353
def factrial(N):
    fc = [1, 1] + [None] * N
    inv = [0, 1] + [None] * N
    fcInv = [1, 1] + [None] * N
    for i in range(2, N+1):
        fc[i] = i*fc[i-1]%mod
        inv[i] = mod-(inv[mod%i]*(mod//i))%mod
        fcInv[i] = fcInv[i-1]*inv[i]%mod
    return fc, fcInv

def modCom(n, k):
    return 0 if n < k else fc[n] * fcInv[k] * fcInv[n-k] % mod

N, M, K = map(int, input().split())
fc, fcInv = factrial(N+1)
ans, C = 0, 0
for k in range(K+1):
    C = modCom(N-1, k)
    C %= mod
    ans += C * M * pow(M-1, N-k-1, mod)
    # print(ans)
    ans %= mod
print(ans)