/* REXX    EASTER                                                               
*/                                                                              
arg years "((" opts                                                             
opts = Strip(opts,"T",")")             /* harvest trailing banana    */         
parse var opts "TRACE" tv .                                                     
parse value tv "O"   with tv  .        /* guarantee a value          */         
rc = Trace(tv)                         /* init trace                 */         
                                                                                
if years = "" then,                                                             
   years = Left(Date("S"),4)                                                    
do while years <> ""                   /* every year                 */         
   parse var years  jhr  years                                                  
   call CALC                           /*                           -*/         
end                                    /* years                      */         
                                                                                
exit                                   /*@ EASTER                    */         
/* ----------------------------------------------------------------- */         
CALC:                                  /*@                           */         
   A = JHR // 19                                                                
   B = JHR // 4                                                                 
   C = JHR // 7                                                                 
   D = (19*A +24) // 30                /* max = 29                   */         
   E = (5 + 2*B + 4*C + 6*D) // 7      /* max =  6                   */         
   DAYS = D + E                        /* max = 35                   */         
   if days > 9 then,                                                            
      SAY "Easter Sunday" JHR "is on" DAYS - 9 "April"    /* 10 - 35 */         
   else,                                                                        
      SAY "Easter Sunday" JHR "is on" DAYS + 22 "March"   /* 1 - 9   */         
return                                 /*@ CALC                      */