program g2;

{$APPTYPE CONSOLE}

uses
  SysUtils,
  Math;

const
  eps = 1e-10;

type
  TEvent = record
    x: Extended;
    typ: Integer;
  end;

var
  a: array [1..100000] of TEvent;
  i, n, point, count, start: Integer;
  r1, r2, pr1, pr2, fi1, fi2: Extended;
  angle, answer: Extended;


procedure sort(l, r: Integer);
var
  i, j: Integer;
  x, w: TEvent;

  function less(x, y: TEvent): Boolean;
  begin
    Result := (x.x < y.x - eps) or (IsZero(x.x - y.x, eps) and (x.typ < y.typ));
  end;

begin
  i := l;
  j := r;
  x := a[(l + r) div 2];
  repeat
    while less(a[i], x) do inc(i);
    while less(x, a[i]) do dec(j);
    if (i <= j) then
    begin
      w := a[i];
      a[i] := a[j];
      a[j] := w;
      inc(i);
      dec(j);
    end;
  until (i > j);
  if (i < r) then sort(i, r);
  if (l < j) then sort(l, j);
end;

procedure intersect(var rr1, rr2: Extended; r1, r2: Extended);
begin
  if (r1 > rr2 - eps) or (rr1 > r2 - eps) then
  begin
    rr1 := 0;
    rr2 := 0;
    Exit;
  end;

  if (rr1 < r1 + eps) and (rr2 > r2 - eps) then
  begin
    rr1 := r1;
    rr2 := r2;
  end;
  if (r1 < rr1 + eps) and (r2 > rr2 - eps) then
  begin
    rr1 := rr1;
    rr2 := rr2;
  end;
  if (rr1 > r1 - eps) and (rr2 > rr2 - eps) then
  begin
    rr1 := rr1;
    rr2 := r2;
  end;
  if (r1 > rr1 - eps) and (r2 > rr2 - eps) then
  begin
    rr1 := r1;
    rr2 := rr2;
  end;

end;

procedure add(a1, a2: Extended);
begin
  if (a1 > a2 + eps) then
  begin
    add(a1, 2 * pi);
    add(0, a2);
    Exit;
  end;
  inc(point);
  a[point].x := a1;
  a[point].typ := 1;

  inc(point);
  a[point].x := a2;
  a[point].typ := -1;
end;

begin
  reset(input, 'input.txt');
  rewrite(output, 'output.txt');

  Readln(n);
  Readln(pr1, pr2, fi1, fi2);
  add(fi2, fi1);
  for i := 1 to n do
  begin
    Readln(r1, r2, fi1, fi2);
    intersect(pr1, pr2, r1, r2);
    if IsZero(r1, eps) and IsZero(r2, eps) then
    begin
      Writeln(0);
      Halt(0);
    end;
    add(fi2, fi1);
  end;

  sort(1, point);

  count := 0;
  angle := 0;
  start := 0;

  for i := 1 to point do
  begin
    if (a[i].typ > 0) then
    begin
      inc(count);
      if (start = 0) then
        start := i;
    end;
    if (a[i].typ < 0) then
      dec(count);

    if (count = 0) then
      angle := angle + (a[i].x - a[start].x);
  end;

  angle := 2 * pi - angle;

  answer := (angle / 2) * (sqr(pr2) - sqr(pr1));

  Writeln(answer: 0: 7);

end.