PROC subnet:
rem 951202, 970528,970915
global n
local p,xp,x,v,mask(4),xxx
mask(1)=255 :mask(2)=255 :mask(3)=255
subn::
cls
print "Mask: 11111111.11111111.11111111.11111100"
print
print "Mask: 255.255.255.252   .248   .240   .224   .192     .0"
print "Antal n„t:         62     30     14      6      2      1"
print "Antal adr. per n„t: 2      6     14     30     62    254"
at 1,17 :print chr$(27),chr$(26),"Esc Meny"
do
 rw::
 v=2**(p+2) :mask(4)=256-v
 at 1,6: print rept$("-",60);"N„tadresser:";
 print "   ";rept$(" ",255)
 at 19+p*7,6 :print "|||"
 at 13,7
 x=v
 if p=5
  at 10,7 :print ": 0" :mask(4)=0
 else
  print " (0)";
  do
   n=key
   if n>0
    if n>257
     if n=290 :text: :goto subn:: :endif
     p=p+(n=259 and p>0)-(n=258 and p<5)
     goto rw::
    endif
   endif
   if x<100
    print " ";
    if x<10 :print " "; :endif
   endif
   print x, :x=x+v
  until x>255-v
  print "(";x;")"
 endif
 at 34,1 :print h$:(mask(4))," /";30-p+(p=5)
 xp=p
 do
  n=get
  if n=290 :text: :goto subn:: :endif
  p=p+(n=259 and p>0)-(n=258 and p<5)
 until xp<>p or n=27
until n=27
ENDP

PROC text:
cls
print
print
print "IP-klass:"
print "A 10. - 171."
print "B 172. - 191."
print "C 192. - 223.255.255.255???"
print "D 224. - 239.255.255.255 multicast"
print "E 240??? ..."
print
print "IP-serier som „r RFC-undantagna:"
print "RFC1597/1627/1918"
print "  1 n„t: 10.0.0.0 - 10.255.255.255"
print " 16 n„t: 172.16.0.0 - 172.31.255.255"
print "256 n„t: 192.168.0.0 - 192.168.255.255"
at 5,17 :print "Esc Meny"
n=get
if n=27 :stop :endif
ENDP

PROC h$:(z)
local b%,c%,s$(8)
b%=256 :c%=z :s$=""
do
 b%=b%/2
 s$=s$+gen$(iabs((c% and b%)>0),1)
until b%=1
return s$
ENDP