unit U_PiCalc1;

.... {Generated code snipped}

Const
inpond:integer=0;  {Number in pond}
totshots:integer=0; {Total number}
radius2= 0.25; {for radius squared}

procedure TForm1.ShootBtnClick(Sender: TObject);
var
i:integer;
  x,y:single;
begin
if strtoint(shotsEdt.text)<high(i) then
for i:= 1 to strtoint(ShotsEdt.text) do
Begin
x:=random- 0.5;  {get random numbers in the range -0.5 to + 0.5}
y:= random - 0.5;
if x*x+y*y < radius2 then inc(inpond);  {distance from center is < 0.5}
{Note: no need to take square root, just compare dist squared to 0.25}
inc(totshots);
end
else showmessage('Max shots exceeded');
  showstats;
end;

procedure TForm1.ResetBtnClick(Sender: TObject);
begin
totshots:=0;
  inpond:=0;
  Showstats;
end;

procedure tform1.showstats;
var r:single;
begin
PondHitsLbl.caption:='Pond Hits '+inttostr(inpond);
  TotShotsLbl.caption:=' Total shots:'+inttostr(totshots);
if totshots>0 then r:= inpond/totshots else r:=0;
begin
RatioLbl.caption:='Ratio of Pond hits to shots '+floattostr(r);
    PiLbl.caption:= 'Pi estimate: '+ floattostr(4*r);
end;
end;

end.