04 Try it yourself Interactive

Compress it, then expand it back

The same address as section 02, one rule application per press. Compress walks all eight groups dropping leading zeros, then finds the zero runs, collapses the longer one, and shows you what happens if you try to collapse both. Expand runs the road backwards from the short form to the full 39 characters. Watch the four counters: characters and hex digits fall on the way down and rise on the way back, and the double-colon counter must never leave 0 or 1. Nothing plays on its own — Next, Back and Reset, or the arrow keys.

Compress · full to short
39 characters, nothing dropped yet
Amber is the group being worked on right now. Indigo is the set of groups the current step is counting — the all-zero runs the :: rule is weighing up on the way down, and the groups still written on the way back. A dashed grey group has been absorbed into a ::. Green is the finished, canonical form; rose is a form that is not legal.
Press Next to begin. Each press applies exactly one rule to exactly one place.


      

        
Characters0

        
Groups shown0

        
Hex digits0

        
Double colons0

      


      

      

        
        
        
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