INSTALL @lib$ + "DATELIB"

      REM The function as per specification.
      DEF FNLongYear(year%)=FN_dow(FN_mjd(1, 1, year%)) == 4 OR FN_dow(FN_mjd(31, 12, year%)) == 4

      REM Demonstrating its use.
      PROCPrintLongYearsInCentury(20)
      PROCPrintLongYearsInCentury(21)
      PROCPrintLongYearsInCentury(22)
      END

      DEF PROCPrintLongYearsInCentury(century%)
      LOCAL year%, start%
      start%=century% * 100 - 100
      PRINT "The long years between ";start% " and ";start% + 100 " are ";
      FOR year%=start% TO start% + 99
        IF FNLongYear(year%) PRINT STR$year% + " ";
      NEXT
      PRINT
      ENDPROC