"The binary sequence s = 111111111000000111111111111111100001 = 1906116041 was generated by a stationary two-state Markov chain with transition probabilities p1|0 =2p0|1 = 0.2. Encode s using
(a.1) a Huffman code for 3-bit symbols based on the source model,
(a.2) a Huffman code for 3-bit symbols based on relative frequencies in s;
(b.1) a Shannon-Fano-Elias code or an arithmetic code for 3-bit symbols based on the source model,"