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nice tricky code there.. and makes sense, but back to generics solution.. how the hell did that work??? it had like a huge hex string...
ivilisation? Ha! I call it as I see it.
I call it bullsh*t, you know, I still cannot believe it
Our evolution now has gone the way of hate
A world evolved resolved into its stupid fate.
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I think that Generics solution worked by having the entire code for the program imbeded in the hex string. The program printed out the contents of the hex string and then then each item of the hex string as a character. I didnt look to closely at it though (fear of brain imploding). Im not sure if Generic wrote it directly or used another program to generate the code (it would be tricky to manually figure out the hex string for printing itself??)
esus saves.... Passes to Moses, shoots, he scores!
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Hi :)
The program stored itself in a hex string as you suggested but the challenge was to get it to fit into less than 255 characters as this is the line limit of QB! ie this:
p$ = "A0868768EF987E..."
had to be less than 255.
It then printed:
print "p$ = "+chr$(34)+p$+chr$(34)
Or something like that. p$ contained the hex for the code for printing p$ (this was generated by another program which scanned through the .bas file). I can't find the code anywhere so I can post it, sorry
:)
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I saw the pi program challenge for newbies, and I thought I'd give it a try... I can calculate it precisely but qbasic only will let me output it to 15 significant figures... help anyone? :???:
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I did this some time ago:
Code: DECLARE SUB BigMul (op1 AS STRING, op2 AS INTEGER)
DECLARE SUB BigAdd (op1 AS STRING, op2 AS STRING)
DECLARE SUB BigSub (op1 AS STRING, op2 AS STRING)
DECLARE SUB BigDiv (op1 AS STRING, op2 AS INTEGER)
DIM SHARED x AS STRING * 512
DIM SHARED x2 AS STRING * 512
DIM SHARED x3 AS STRING * 512
DIM SHARED x4 AS STRING * 512
CLS
x = CHR$(1) + CHR$(0) + STRING$(510, 0)
BigDiv x, 5
x3 = x
PRINT "Calculating atn(1/5):";
FOR a = 0 TO 878
LOCATE 1, 22: PRINT a + 1; "/ 879"
BigDiv x, 25
x2 = x
BigDiv x2, a * 2 + 3
IF a AND 1 THEN
BigAdd x3, x2
ELSE
BigSub x3, x2
END IF
NEXT a
x = CHR$(1) + CHR$(0) + STRING$(510, 0)
BigDiv x, 239
x4 = x
PRINT "Calculating atn(1/239):";
FOR a = 0 TO 257
LOCATE 2, 24: PRINT a + 1; "/ 258"
BigDiv x, 239
BigDiv x, 239
x2 = x
BigDiv x2, a * 2 + 3
IF a AND 1 THEN
BigAdd x4, x2
ELSE
BigSub x4, x2
END IF
NEXT a
BigMul x3, 4
BigSub x3, x4
BigMul x3, 4
PRINT "PI = ";
FOR t% = 1 TO 1000
PRINT LTRIM$(STR$(ASC(MID$(x3, 1, 1)) MOD 10));
IF t% = 1 THEN PRINT ".";
MID$(x3, 1, 1) = CHR$(0)
BigMul x3, 10
NEXT t%
SUB BigAdd (op1 AS STRING, op2 AS STRING)
carry& = 0
FOR c% = 511 TO 1 STEP -2
add1& = CVL(MID$(op1, c%, 2) + CHR$(0) + CHR$(0))
add2& = CVL(MID$(op2, c%, 2) + CHR$(0) + CHR$(0))
thing& = add1& + add2& + carry&
IF thing& > 65536 THEN
thing& = thing& - 65536
carry& = 1
ELSE
carry& = 0
END IF
IF thing& > 32767 THEN thing& = thing& - 65536
MID$(op1, c%, 2) = MKI$(thing&)
NEXT c%
END SUB
SUB BigDiv (op1 AS STRING, op2 AS INTEGER)
numq& = CVL(MID$(op1, 1, 2) + CHR$(0) + CHR$(0)) \ op2
numr& = CVL(MID$(op1, 1, 2) + CHR$(0) + CHR$(0)) MOD op2
MID$(op1, 1, 1) = CHR$(numq& AND 255)
MID$(op1, 2, 1) = CHR$(numq& \ 256)
nextval$ = CHR$(numr& AND 255) + CHR$(numr& \ 256)
FOR c% = 3 TO 511 STEP 2
numq& = CVL(MID$(op1, c%, 2) + nextval$) \ op2
numr& = CVL(MID$(op1, c%, 2) + nextval$) MOD op2
MID$(op1, c%, 1) = CHR$(numq& AND 255)
MID$(op1, c% + 1, 1) = CHR$(numq& \ 256)
nextval$ = CHR$(numr& AND 255) + CHR$(numr& \ 256)
NEXT c%
END SUB
SUB BigMul (op1 AS STRING, op2 AS INTEGER)
carry& = 0
FOR c% = 511 TO 1 STEP -2
mul& = CVL(MID$(op1, c%, 2) + CHR$(0) + CHR$(0))
thing& = mul& * op2 + carry&
carry& = thing& \ 65536
thing& = thing& AND 65535
IF thing& > 32767 THEN thing& = thing& - 65536
MID$(op1, c%, 2) = MKI$(thing&)
NEXT c%
END SUB
SUB BigSub (op1 AS STRING, op2 AS STRING)
borrow& = 0
FOR c% = 511 TO 1 STEP -2
sub1& = CVL(MID$(op1, c%, 2) + CHR$(0) + CHR$(0))
sub2& = CVL(MID$(op2, c%, 2) + CHR$(0) + CHR$(0))
thing& = sub1& - sub2& - borrow&
IF thing& < 0 THEN
thing& = thing& + 65536
borrow& = 1
ELSE
borrow& = 0
END IF
IF thing& > 32767 THEN thing& = thing& - 65536
MID$(op1, c%, 2) = MKI$(thing&)
NEXT c%
END SUB
Posts: 3,343
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Joined: Mar 2003
Damn... if it is getting that tricky then it probably isn't a problem for newbies... :???: :???: I don't understand what is happening in there. The way I calculate pi is like this: pi = 4 * ATN(1). This is pi exactly but can only be printed to 15 s.f.
Mofu, have you solved it?
Or Neo???
ps: when I tried to modify your prog to calculate pi to 10000 places someone42, it started printing zeroes after a while. What have I done wrong? Or is it a message from aliens.. :rotfl:
I can make a program that prints its source in 4 lines, but it uses files...  )
Here is a program that encrypts a string, and can decrypt it again. Any queries, suggestions etc I would appreciate
Code: ' -- Encryption Program --
' - By The Oracle -
' This program takes an inputted string and encodes it to a file. You can
' also use this program to decode. It is based on a simple encoding
' technique, "using a keyword". Basically even if the numbers in the file
' are the same they could be two different letters because every letter
' is encoded differently.
DECLARE SUB getkeywords ()
DIM SHARED keywords(1 TO 5) AS STRING
RANDOMIZE TIMER
getkeywords
CLS
LOCATE 10, 15
COLOR 9
PRINT "Welcome to The Oracle's Encryption Program"
LOCATE 12, 25
COLOR 15
PRINT "1) Encrypt message"
LOCATE 13, 25
PRINT "2) Decrypt message"
LOCATE 14, 25
PRINT "3) Exit"
LOCATE 16, 25
INPUT "Your choice? ", choice$
IF choice$ = "1" THEN
GOTO encryption
ELSEIF choice$ = "2" THEN
GOTO decryption
ELSEIF choice$ = "3" THEN
END
ELSEIF choice$ = CHR$(27) THEN
END
ELSE
RUN
END IF
' I wouldn't normally use GOTO, but you can't redim arrays when inside
' subroutines as far as I am aware... Anyone know how???
encryption:
CLS
k = INT(RND * 5) + 1
FOR a = 1 TO LEN(keywords(k))
codes(a) = ASC(MID$(keywords(k), a, 1)) ' Store the ASCII codes in an array
NEXT a
INPUT "Type a string you want to encrypt: ", encrypt$
IF encrypt$ = CHR$(27) THEN END
INPUT "Type a name for the file the info is stored in: ", filename$
IF filename$ = CHR$(27) THEN END
IF RIGHT$(filename$, 4) <> ".txt" THEN filename$ = filename$ + ".txt"
DIM SHARED enc(1 TO LEN(encrypt$)) AS INTEGER
OPEN filename$ FOR OUTPUT AS #1
FOR b = 1 TO LEN(encrypt$) ' For each character
IF b > LEN(keywords(k)) + c THEN c = c + LEN(keywords(k)) ' If the character
' number is greater
' than the keyword
' start from the
' start of the keyword
enc(b) = ASC(MID$(encrypt$, b, 1)) + codes(b - c) ' This is simple encoding
PRINT #1, STR$(enc(b)) ' Print to file
NEXT b
CLOSE
PRINT "Your key is"; k; ". Don't lose it!!!"
WHILE INKEY$ = "": WEND
RUN
decryption:
CLS
INPUT "Enter your keycode: ", k
INPUT "Enter the filename: ", filename$
IF RIGHT$(filename$, 4) <> ".txt" THEN filename$ = filename$ + ".txt"
OPEN filename$ FOR INPUT AS #1
DO UNTIL EOF(1) ' This loop simply counts the number of lines
INPUT #1, a$
d = d + 1
LOOP
CLOSE ' How do you reposition the cursor at the beginning of a file?
' I've used CLOSE and OPEN
OPEN filename$ FOR INPUT AS #1
DIM decodes(1 TO d) AS INTEGER ' Array for storing the codes from the file
FOR o = 1 TO d ' Get the numbers in the file
INPUT #1, a%
decodes(o) = a%
NEXT o
FOR a = 1 TO LEN(keywords(k)) ' Get the codes of the keyword
codes(a) = ASC(MID$(keywords(k), a, 1))
NEXT a
DIM SHARED enc(1 TO d) AS INTEGER ' Array for the actual message
FOR l = 1 TO d
IF l > LEN(keywords(k)) + c THEN c = c + LEN(keywords(k))
enc(l) = decodes(l) - codes(l - c) ' Decode the string
PRINT CHR$(enc(l)); ' Print the result
NEXT l
WHILE INKEY$ = "": WEND
RUN
END
SUB getkeywords
keywords(1) = "roast"
keywords(2) = "qbasic"
keywords(3) = "mouse"
keywords(4) = "oracle"
keywords(5) = "algorithm"
END SUB
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Quote:The way I calculate pi is like this: pi = 4 * ATN(1)
That's exactly what I do, just with higher precision calculations that allow more than 17 digits.
Oh yeah and I got this from some site:
atn(1) = 4 * atn(1/5) - atn(1/239)
Quote:when I tried to modify your prog to calculate pi to 10000 places someone42, it started printing zeroes after a while
Are you just changing the "FOR t% = 1 to 1000" line? The numbers I use are 4096-bit numbers, which can hold 1233 decimal digits. You have to change other things. I have tried to get it to give 10000 digits but for some utterly strange reason after about 2000 digits everything is *wrong*.
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Threads: 83
Joined: Mar 2003
Maybe because qbasic works in binary...
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