The answer is in the switch(c). If the decompressor receives an entry 0, 1 or 2 it has a special meaning. All other entries IDs are to be taken from the dictionary. 0 means it's followed by an 8 bit entity. 1 by a 16 bit entity. 2 means it's the end of the stream. So put whatever you want in the first three entries, the code will never read from it. Or don't put anything. But start appending to your dictionary at index 3.
Let me know if you still have issues.
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