var n,m,i,j:longint;
a,b:array[1..30] of longint;
begin
  assign(input,'ballg.in');
  assign(output,'ballg.out');
  reset(input);
  rewrite(output);
  readln(n,m);
  a[1]:=1;
  for j:=2 to n do
    a[j]:=0;
  b:=a;
  for i:=1 to m-1 do
    begin
      a[1]:=b[n]+b[2];
      for j:=2 to n-1 do
        a[j]:=b[j-1]+b[j+1];
      a[n]:=b[n-1]+b[1];
      b:=a;
    end;
  writeln(b[n]+b[2]);
  close(input);
  close(output);
end.