SCREEN 0: DEFDBL A-Z
DO
   CLS : LOCATE 1, 1: COLOR 12: PRINT "Immettere una data: "
   LOCATE 1, 21: COLOR 10: PRINT CHR$(95);
   Token$ = ""
10 DO
      One = ASC(INPUT$(1))
   LOOP UNTIL One = 48 OR One = 49 OR One = 50 OR One = 51
   Token$ = CHR$(One)
   LOCATE 1, 21: COLOR 10: PRINT Token$ + CHR$(95);
20 IF One = 51 THEN
      DO
         Two = ASC(INPUT$(1))
      LOOP UNTIL Two = 48 OR Two = 49 OR Two = 8
   ELSE
      DO
         Two = ASC(INPUT$(1))
      LOOP UNTIL Two >= 48 AND Two <= 57 OR Two = 8
   END IF
   IF Two = 8 THEN
      LOCATE 1, 21: PRINT CHR$(95) + CHR$(32);
      GOTO 10
   END IF
   Token$ = Token$ + CHR$(Two)
   LOCATE 1, 22: PRINT RIGHT$(Token$, 1) + CHR$(47) + CHR$(95);
   D = VAL(Token$)
30 DO
      Three = ASC(INPUT$(1))
   LOOP UNTIL Three = 48 OR Three = 49 OR Three = 8
   IF Three = 8 THEN
      LOCATE 1, 22: PRINT CHR$(95) + SPACE$(2);
      Token$ = LEFT$(Token$, 1)
      GOTO 20
   END IF
   Token$ = Token$ + CHR$(Three)
   LOCATE 1, 24: PRINT RIGHT$(Token$, 1) + CHR$(95);
40 DO
      Flag = 0
      Four = ASC(INPUT$(1))
      M = VAL(RIGHT$(Token$ + CHR$(Four), 2))
      IF Four < 48 OR Four > 57 THEN Flag = 1
      IF Three = 49 AND Four > 50 THEN Flag = 1
      IF D > 29 AND M = 2 THEN Flag = 1
      IF D = 31 AND (M = 4 OR M = 6 OR M = 9 OR M = 11) THEN Flag = 1
      IF Four = 8 THEN
         LOCATE 1, 24: PRINT CHR$(95) + CHR$(32);
         Token$ = LEFT$(Token$, 2)
         GOTO 30
      END IF
   LOOP UNTIL Flag <> 1
   Token$ = Token$ + CHR$(Four)
   LOCATE 1, 25: PRINT RIGHT$(Token$, 1) + CHR$(47) + CHR$(95);
50 DO
      Five = ASC(INPUT$(1))
   LOOP UNTIL Five >= 48 AND Five <= 57 OR Five = 45 OR Five = 8
   IF Five = 8 THEN
      LOCATE 1, 25: PRINT CHR$(95) + SPACE$(2);
      Token$ = LEFT$(Token$, 3)
      GOTO 40
   END IF
   Token$ = Token$ + CHR$(Five)
   Year$ = CHR$(Five)
   LOCATE 1, 27: PRINT RIGHT$(Token$, 1) + CHR$(95);
   DO
      Nul = 0: Sign = 0
      DO
         Flag = 0
         Six = ASC(INPUT$(1))
         Year$ = Year$ + CHR$(Six)
         IF Six <> 13 AND (Six < 48 OR Six > 57) THEN Year$ = LEFT$(Year$, LEN(Year$) - 1): Flag = 1
         IF Year$ = CHR$(45) + CHR$(13) OR Year$ = CHR$(45) + CHR$(48) THEN Year$ = LEFT$(Year$, LEN(Year$) - 1): Flag = 1
         IF ABS(VAL(Year$)) > 5000000 THEN Year$ = LEFT$(Year$, LEN(Year$) - 1): Flag = 1
         IF VAL(Year$) < -46 AND D > 28 AND M = 2 THEN Year$ = LEFT$(Year$, LEN(Year$) - 1): Flag = 1
         IF Flag <> 1 AND Six <> 13 THEN LOCATE 1, 26 + LEN(Year$): PRINT CHR$(Six) + CHR$(95);
         IF Flag <> 1 AND Six = 13 THEN LOCATE 1, 26 + LEN(Year$): PRINT CHR$(32);
         IF Six = 8 AND LEN(Year$) = 1 THEN
            LOCATE 1, 27: PRINT CHR$(95) + CHR$(32);
            Token$ = LEFT$(Token$, 4)
            GOTO 50
         END IF
         IF Six = 8 AND LEN(Year$) > 1 THEN
            Year$ = LEFT$(Year$, LEN(Year$) - 1)
            LOCATE 1, 27 + LEN(Year$): PRINT CHR$(95) + CHR$(32);
         END IF
      LOOP UNTIL Six = 13 AND Flag <> 1
      Token$ = Token$ + MID$(Year$, 2): Y = VAL(Year$)
      IF Y / 4 <> INT(Y / 4) AND D = 29 AND M = 2 THEN Sign = 1
      IF Y > 1500 AND Y / 100 = INT(Y / 100) AND Y / 400 <> INT(Y / 400) AND D = 29 AND M = 2 THEN Sign = 1
      IF Y = 1582 AND M = 10 AND (D > 4 AND D < 15) THEN Sign = 1
      IF Sign = 1 THEN
         Nul = 1
         Year$ = LEFT$(Year$, LEN(Year$) - 1)
         LOCATE 1, 27 + LEN(Year$): PRINT CHR$(95);
      END IF
   LOOP UNTIL Nul <> 1
   IF Y >= 0 THEN
      SELECT CASE M
         CASE 1
            Token = (Y - 1) * 365 + INT((Y - 1) / 4) + D
         CASE 2
            Token = (Y - 1) * 365 + INT((Y - 1) / 4) + 31 + D
         CASE 3
            Token = (Y - 1) * 365 + INT(Y / 4) + 59 + D
         CASE 4
            Token = (Y - 1) * 365 + INT(Y / 4) + 90 + D
         CASE 5
            Token = (Y - 1) * 365 + INT(Y / 4) + 120 + D
         CASE 6
            Token = (Y - 1) * 365 + INT(Y / 4) + 151 + D
         CASE 7
            Token = (Y - 1) * 365 + INT(Y / 4) + 181 + D
         CASE 8
            Token = (Y - 1) * 365 + INT(Y / 4) + 212 + D
         CASE 9
            Token = (Y - 1) * 365 + INT(Y / 4) + 243 + D
         CASE 10
            Token = (Y - 1) * 365 + INT(Y / 4) + 273 + D
         CASE 11
            Token = (Y - 1) * 365 + INT(Y / 4) + 304 + D
         CASE 12
            Token = (Y - 1) * 365 + INT(Y / 4) + 334 + D
      END SELECT
      IF Y > 1582 THEN
         Minus = -1
         FOR K = 1500 TO Y STEP 100
            IF K / 400 <> INT(K / 400) THEN Minus = Minus + 1
         NEXT
         Token = Token - Minus - 10
      END IF
      IF Y = 1582 AND M > 10 THEN
         Token = Token - 10
      ELSE
         IF Y = 1582 AND M = 10 AND D >= 15 THEN Token = Token - 10
      END IF
      Token = Token + 366
      LOCATE 1, 21: PRINT SPACE$(32);
      LOCATE 1, 21: SELECT CASE Token MOD 7
         CASE 0
            PRINT "Mercoled¨";
         CASE 1
            PRINT "Gioved¨";
         CASE 2
            PRINT "Venerd¨";
         CASE 3
            PRINT "Sabato";
         CASE 4
            PRINT "Domenica";
         CASE 5
            PRINT "Luned¨";
         CASE 6
            PRINT "Marted¨";
      END SELECT
   ELSE
      SELECT CASE M
         CASE 1
            Token = (Y + 1) * 365 - 365 + D
         CASE 2
            Token = (Y + 1) * 365 - 334 + D
         CASE 3
            Token = (Y + 1) * 365 - 306 + D
         CASE 4
            Token = (Y + 1) * 365 - 275 + D
         CASE 5
            Token = (Y + 1) * 365 - 245 + D
         CASE 6
            Token = (Y + 1) * 365 - 214 + D
         CASE 7
            Token = (Y + 1) * 365 - 184 + D
         CASE 8
            Token = (Y + 1) * 365 - 153 + D
         CASE 9
            Token = (Y + 1) * 365 - 122 + D
         CASE 10
            Token = (Y + 1) * 365 - 92 + D
         CASE 11
            Token = (Y + 1) * 365 - 61 + D
         CASE 12
            Token = (Y + 1) * 365 - 31 + D
      END SELECT
      IF Y > -46 THEN
         IF M <= 2 THEN
            Token = Token + FIX(Y / 4)
         ELSE
            Token = Token + FIX((Y + 1) / 4)
         END IF
      ELSE
         Token = Token - 11
      END IF
      LOCATE 1, 21: PRINT SPACE$(32);
      LOCATE 1, 21: SELECT CASE ABS(Token - 1) MOD 7
         CASE 0
            PRINT "Gioved¨";
         CASE 1
            PRINT "Mercoled¨";
         CASE 2
            PRINT "Marted¨";
         CASE 3
            PRINT "Luned¨";
         CASE 4
            PRINT "Domenica";
         CASE 5
            PRINT "Sabato";
         CASE 6
            PRINT "Venerd¨";
      END SELECT
   END IF
   PRINT CHR$(44); D;
   RESTORE
   FOR I = 1 TO M
      READ Month$
   NEXT
   DATA gennaio, febbraio, marzo, aprile, maggio, giugno, luglio, agosto, settembre, ottobre, novembre, dicembre
   PRINT Month$; ABS(Y);
   IF Y > 0 THEN PRINT "d.C."
   IF Y < 0 THEN PRINT "a.C."
   LOCATE 2, 1: COLOR 12: PRINT "Giorno assoluto:";
   IF Token - 1 < 0 THEN PRINT CHR$(32);
   COLOR 10: IF Token > 0 THEN PRINT Token;  ELSE PRINT Token - 1;
   LOCATE 3, 1: COLOR 12: PRINT "Operatore: ";
   DO
      LOCATE 3, 12: PRINT CHR$(32);
      LOCATE 3, 12: COLOR 10: PRINT CHR$(95);
      Sym$ = INPUT$(1)
   LOOP UNTIL Sym$ = CHR$(42) OR Sym$ = CHR$(43) OR Sym$ = CHR$(45) OR Sym$ = CHR$(27) OR Sym$ = CHR$(13)
   IF Sym$ <> CHR$(13) AND Sym$ <> CHR$(27) THEN
      LOCATE 3, 12: PRINT Sym$;
      LOCATE 4, 1: COLOR 12: PRINT "Variazione o fattore: ";
      LOCATE 4, 23: COLOR 10: PRINT CHR$(95);
60    DO
         One$ = INPUT$(1)
      LOOP WHILE (ASC(One$) < 49 OR ASC(One$) > 57) AND ASC(One$) <> 45
      Incr$ = One$
      LOCATE 4, 23: PRINT One$ + CHR$(95);
      DO
         Flag1 = 0
         DO
            One$ = INPUT$(1)
         LOOP WHILE (ASC(One$) < 48 OR ASC(One$) > 57) AND ASC(One$) <> 8 AND ASC(One$) <> 13
         IF One$ = CHR$(8) THEN
            LOCATE 4, 23: PRINT CHR$(95) + CHR$(32);
            GOTO 60
         END IF
         IF (Incr$ = CHR$(45) AND One$ = CHR$(48)) OR (Incr$ = CHR$(45) AND One$ = CHR$(13)) THEN
            Flag1 = 1
         ELSE
            Incr$ = Incr$ + One$
            LOCATE 4, 24: PRINT One$ + CHR$(95);
         END IF
      LOOP UNTIL Flag1 <> 1
      IF RIGHT$(Incr$, 1) <> CHR$(13) THEN
         DO
            DO
               Two$ = INPUT$(1)
            LOOP WHILE ASC(Two$) <> 13 AND (ASC(Two$) < 48 OR ASC(Two$) > 57) AND ASC(Two$) <> 8
            IF Two$ <> CHR$(13) AND Two$ <> CHR$(8) THEN Incr$ = Incr$ + Two$
            IF Two$ <> CHR$(8) THEN
               LOCATE 4, 22 + LEN(Incr$)
               IF Two$ <> CHR$(13) THEN PRINT Two$ + CHR$(95);
            END IF
            IF Two$ = CHR$(8) AND LEN(Incr$) = 1 THEN
               Incr$ = ""
               LOCATE 4, 23: PRINT CHR$(95) + CHR$(32);
               GOTO 60
            END IF
            IF Two$ = CHR$(8) AND LEN(Incr$) > 1 THEN
               Incr$ = LEFT$(Incr$, LEN(Incr$) - 1)
               LOCATE 4, 23 + LEN(Incr$): PRINT CHR$(95) + CHR$(32);
            END IF
         LOOP WHILE ASC(Two$) <> 13
      ELSE
         LOCATE 4, 24: PRINT CHR$(32);
      END IF
      LOCATE 4, 23 + LEN(Incr$): PRINT CHR$(32);
      Incr = VAL(Incr$)
      IF Sym$ = CHR$(42) THEN
         IF Token <= 0 THEN
            Day = (Token - 1) * Incr
         ELSE
            Day = Token * Incr
         END IF
      END IF
      IF Sym$ = CHR$(43) THEN
         Day = Token + Incr
         IF Day <= 0 THEN Day = Day - 1
      END IF
      IF Sym$ = CHR$(45) THEN
         Day = Token - Incr
         IF Day <= 0 THEN Day = Day - 1
      END IF
      LOCATE 5, 1: COLOR 12: PRINT "Data finale:";
      LOCATE 5, 13: COLOR 10
      IF Day > 0 THEN PRINT Day;
      IF Day < 0 THEN PRINT CHR$(32); Day;
   ELSE
      LOCATE 3, 1: PRINT SPACE$(12);
   END IF
   DO
      LOCATE 7, 1: COLOR 12: PRINT "Altra immissione [S/N]?";
      LOCATE 7, 25: COLOR 10: PRINT CHR$(95);
      Again$ = INPUT$(1)
   LOOP UNTIL Again$ = CHR$(78) OR Again$ = CHR$(83) OR Again$ = CHR$(110) OR Again$ = CHR$(115)
   LOCATE 7, 25: PRINT Again$;
LOOP UNTIL Again$ = CHR$(78) OR Again$ = CHR$(110)
PRINT : END