var       s: int64;
    k, i, n: longint;

procedure c(n, k: longint);
 begin
  s := 1;
  for i := n - k + 1 to n do
   s := s * i;
  for i := 1 to k do
   s := s div i;
 end;

begin
 read(n, k);
 c(n + k - 1, k - 1);
 write(s);
end.