DAYS:PROCEDURE
/* We've no less days... */
/* Proc returns number of days in specific month */
ARG MM,YY
IF LENGTH(YY)=2 THEN DO
   IF YY>80 THEN YY='19'YY
   ELSE YY='20'YY
END

IF MM=2 THEN RETURN 28+LEAP(YY)
/* Dni Ada */
AD='31 28 31 30 31 30 31 31 30 31 30 31'
RETURN WORD(AD,MM)

/***GET LEAP */
LEAP:PROCEDURE
/* Return 1 if parm is leap year */
ARG YY
IF LENGTH(YY)=2 THEN DO
   IF YY>80 THEN YY='19'YY
   ELSE YY='20'YY
END
RETURN (YY%4*4=YY)