program ESTRPSAK { www.merlyn.demon.co.uk >= 2001-09-26
  cf Remy Landau E-mails Aug 2001 } ;

{ IN:  HEBPESAK.DAT : each line is four numbers -
  .    Gregorian Year, Month, and Day of Pesach, and 1 for Sunday
  .    Hebrew Pesach = Passover = 15 Nisan
  OUT: HEBPESAK.OUT :
  .    Gregorian Y M D of Pesach;
  .      M D of G Easter, comparison; M D of J Easter, comparison }

uses DateProx ;

var F, G : text ; MJD : MJdate ; QY : integer ;
PY, PM, PD, PW : word ; GM, GD, JM, JD : byte ;

procedure Report ;
const
Lt = '<    ' ;
Eq = '  =  ' ;
Gt = '    >' ;
Sgn : array [boolean] of string [5] = (Lt, Gt) ;
var Q : integer ; S : string [5] ;
begin
  Q := integer(PM*40+PD) - integer(GM*40+GD) ;
  if Q=0 then S := Eq else S := Sgn[Q>0] ;
  Write(G, GM:4, GD:3, '':3, S) end {Report} ;


const DoW : array [0..7] of string [2] =
  ('Sa', 'Su', 'Mo', 'Tu', 'We', 'Th', 'Fr', 'Sa') ;

procedure Head ;
begin Writeln(G, ^M^J,
  ' Year  Hebrew  D   Greg          Julian       '^M^J,
  '       Pesach  o  Easter    G    Easter    J  '^M^J,
  ' Greg   Greg   W  Sunday  P<=>E  Sunday  P<=>E'^M^J) end {Head} ;


BEGIN ;
Assign(F, 'HEBPESAK.DAT') ; Reset(F) ;
Assign(G, 'HEBPESAK.ouT') ; Rewrite(G) ;
Writeln(G, ^M^J, 'Ordering of Pesach and Easters':39, ^M^J,
  ^M^J, 'All dates are Gregorian':36, ^M^J) ;
Head ;
while not EoF(F) do begin
  Readln(F, PY, PM, PD, PW) ;
  Write(G, PY:5, PM:4, PD:3, DoW[PW]:4) ;
  Easter(PY, GM, GD) ;
  Report ;
  OldEaster(PY, JM, JD) ;
  MJD := YMD_to_MJD(JulCal, PY, JM, JD) ;
  MJDtoYMD(MJD, QY, GM, GD) ;
  Report ;
  Writeln(G) end ;
Head ;
Writeln(G, ^M^J, '------':26) ;
Close(G) ; Close(F) ;
END.