Olimpiade Sains Provinsi (OSP) 2015 - Komputer, Nomor 43–44

function D(X,Y : integer) : integer;
begin
      if (Y = 0) then D := 1
      else D := Y+1;
end;

function C(X,Y : integer) : integer;
begin
      if (Y = 0) then C := X
      else C := D(X,C(X,Y-1));
end;

function B(X,Y : integer) : integer;
begin
      if (Y = 0) then B := 0
      else B := C(X,B(X,Y-1));
end;

function A(X,Y : integer) : integer;
begin
      if (Y = 0) then A := 1
      else A := B(X,A(X,Y-1));
end;

begin
      writeln(A(4,2));
end.