program zonder;

var
  deel,tel : integer;

procedure verdeel(r : double; var x,y : double);
var
  geval : boolean;
begin
  geval := (0 < r) and (r <= 1/4);
  if geval then
  begin
    x := 0; y := r*4;
  end;
  geval := (1/4 < r) and (r <= 1/2);
  if geval then
  begin
    y := 1; x := (r-1/4)*4;
  end;
  geval := (1/2 < r) and (r <= 3/4);
  if geval then
  begin
    x := 1; y := (r-1/2)*4;
  end;
  geval := (3/4 < r) and (r <= 1);
  if geval then
  begin
    y := 0; x := (r-3/4)*4;
  end;
end;

procedure test;
var
  x1,y1,x2,y2,x3,y3 : double;
  D,xi,eta,T,xm,ym : double;
begin
  verdeel(Random,x1,y1);
  verdeel(Random,x2,y2);
  verdeel(Random,x3,y3);
  xm := 1/2; ym := 1/2;
  tel := tel + 1;
  D := (x2-x1)*(y3-y1)-(x3-x1)*(y2-y1);
  if D = 0 then Exit;
  xi := (xm-x1)*(y3-y1)-(x3-x1)*(ym-y1);
  eta := (x2-x1)*(ym-y1)-(xm-x1)*(y2-y1);
  xi := xi/D; eta := eta/D;
  T := 1-xi-eta;
  if xi < T then T := xi;
  if eta < T then T := eta;
  If T > 0 then deel := deel + 1;
  Writeln(deel/tel);
end;

begin
  tel := 0;
  deel := 0;
  while true do
  begin
    test;
  end;
end.