new_contents: from sys import stdin
  
  N, K = [int(x) for x in stdin.readline().split()]
  
  if K == 1:
      print(1)
      exit()
  
  currentEnd = [1] * (N + 1)
  for _ in range(K - 2):
      nextEnd = [sum(currentEnd[x:]) for x in range(N + 1)]
      currentEnd = nextEnd
  
  print(sum(currentEnd) % 1000000000)
subject: solve problem no.2225