import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes");YES = lambda : print("YES")
no = lambda :print("no");No = lambda :print("No");NO = lambda : print("NO")
#######################################################################

n, k = na()
mod = 998244353
def find_coefficient(N, k, MOD=998244353):
    # Initialize the coefficients array
    a = [0] * (N + 1)
    a[0] = 1  # a_0 = 1

    # Compute the coefficients using the recurrence relation
    for n in range(1, N + 1):
        a[n] = a[n - 1]
        if n >= k:
            a[n] = (a[n] + a[n - k]) % MOD

    return a[N]

print(find_coefficient(n, k))