Problem
1. Suppose that the frequencies of the occurrence of all the characters to be en-coded are different. Is the Huffman encoding tree unique?
2. Huffman coding could be extended in a straightforward way to encode in two-bit characters (using 4-way trees). What would be the main advantage and the main disadvantage of doing so?
3. What would be the result of breaking up a Huffman-encoded string into five-bit characters and Huffman-encoding that string?
4. Implement a procedure to decode a Huffman-encoded string, given the code and len arrays.