function checkMove(key1:char):boolean;
begin
   if key1=#0 then begin
   case key1 of
      chr(75):
      begin
        if pile[pacY][pacX-1].isitwall=false then checkmove:=true else checkmove:=false;
      end;
      chr(77):
      begin
        if pile[pacY][pacX+1].isitwall=false then checkmove:=true else checkmove:=false;
      end;
      chr(72):
      begin
        if pile[pacY-1][pacX].isitwall=false then checkmove:=true else checkmove:=false;
      end;
      chr(80):
      begin
        if pile[pacY+1][pacX].isitwall=false then checkmove:=true else checkmove:=false;
      end;
    end;
   end;
end;



function readInput():char;
begin
  if keypressed then key:=readkey;
  begin
    if key=#0 then begin
    if checkmove(key)=true then key:=readkey
    else key:=previouskey;
    end;
    case key of
      chr(75):
      begin
        if pile[pacY][pacX-1].isitwall=false then
        begin
          readInput:='a';  // lewo
          pacX:=pacX-1;

        end;
      end;
      chr(77):
      begin
        if pile[pacY][pacX+1].isitwall=false then
        begin
          readInput:='d';
          pacX:=pacX+1; // prawo

        end else readinput:=previouskey;
      end;
      chr(72):
      begin
        if pile[pacY-1][pacX].isitwall=false then
        begin
          readInput:='w';      //gora
          pacY:=pacY-1;
        end;
      end;
      chr(80):
      begin
        if pile[pacY+1][pacX].isitwall=false then
        begin
          readInput:='s';        //dol
          pacY:=pacY+1;

        end;
      end;
    end;
  end;
  writeln(key,' ',previouskey);
  previouskey:=key;
end;