cls
input "Texte   ",x$
print "texte : " +x$
print
deb:
print "Coder: tapez 1"
print "Décoder: tapez 2"
input cd
if cd=1 then gosub code
if cd=2 then gosub decode
print cd
goto deb
end
code:
a$=x$
t = length(a$)


print "Codage"
for i=1 to t
 t$= mid(a$,i,1)
t1=asc(t$)
#algorithme de cryptage 
x=(t1+5)

print chr(x);
next i
print
end
return


decode:
b$=x$
v2 = length(b$)
print  "------------------------"
print"Décodage"
for i=1 to v2
v$= mid(b$,i,1)
t2=asc(v$)

#algorithme de décryptage 
y=(t2-5)
print chr(y);
next i
end
return