Changing letters

[Lanzaa]

Well i changed both with that except i can't figure out in 5 min how to decode so im going to try tomarrow here are the codes :lol:

Code:

CLS
INPUT "sentence test"; a$
FOR letter = 1 TO LEN(a$)
b = ASC(MID$(a$, letter, 1))
SELECT CASE b
    CASE 65 to 90
        b = (((b - 65) + 1) MOD 26) + 65
    CASE 97 to 122
        b = (((b - 97) + 1) MOD 26) + 97
END SELECT
MID$(a$, letter, 1) = CHR$(b)
NEXT letter
PRINT a$

Code:

CLS
start: INPUT "Encode or decode"; f$
g = 0
CLS
INPUT "Input sentence"; a$
code: CLS
PRINT a$
FOR letter = 1 TO LEN(a$)
IF f$ = "decode" THEN number = (26 - (letter MOD 26))
IF f$ = "encode" THEN number = (letter MOD 26)
b = ASC(MID$(a$, letter, 1))
SELECT CASE b
    CASE 65 TO 90
        b = (((b - 65) + number) MOD 26) + 65
    CASE 97 TO 122
        b = (((b - 97) + number) MOD 26) + 97
END SELECT
MID$(a$, letter, 1) = CHR$(b)
NEXT letter
PRINT a$
PRINT
IF f$ = "encode" THEN INPUT "Do you want to decode? y / n "; f$
IF f$ = "y" THEN
    f$ = "decode"
    GOTO code
END IF
PRINT
INPUT "Again? y / n "; f$
IF f$ = "y" THEN
    CLS
    GOTO start
END IF

tx all