Caesar cipher: Difference between revisions

==={{header|Chipmunk Basic}}===

{{works with|Chipmunk Basic|3.6.4}}

{{trans|BASIC256}}

<syntaxhighlight lang="qbasic">

10 rem Caesar cipher

20 cls

30 dec$ = ""

40 type$ = "cleartext "

50 print "If decrypting enter "+"<d> "+" -- else press enter "; : input dec$

60 input "Enter offset > ",ioffset

70 if dec$ = "d" then

80 ioffset = 26-ioffset

90 type$ = "ciphertext "

100 endif

110 print "Enter "+type$+"> ";

120 input cad$

130 cad$ = ucase$(cad$)

140 longitud = len(cad$)

150 for i = 1 to longitud

160 itemp = asc(mid$(cad$,i,1))

170 if itemp > 64 and itemp < 91 then

180 itemp = ((itemp-65)+ioffset) mod 26

190 print chr$(itemp+65);

200 else

210 print chr$(itemp);

220 endif

230 next i

240 print

250 end

</syntaxhighlight>

{{OUT}}

<pre> >run

If decrypting enter <d> -- else press enter ?

Enter offset > 21

Enter cleartext > ? My hovercraft is full of eels.

HT CJQZMXMVAO DN APGG JA ZZGN.

>run

If decrypting enter <d> -- else press enter ? d

Enter offset > 21

Enter ciphertext > ? HT CJQZMXMVAO DN APGG JA ZZGN.

MY HOVERCRAFT IS FULL OF EELS.</pre>