Frequencies:
    a: 3
    b: 2
    c: 1

Construct the Tree:
    <- [c, b, a]
    <- [a, *   ]
          / \
         c   b

        *
       / \
      a   *
         / \
        c   b

Get Codes:
    a is 0
    b is 11
    c is 10


Compress cbbaaa:
    c   b  b  a a a
    10  11 11 0 0 0

    101111000

Decompress 101111000:
    10 11 11 0 0 0
    c  b  b  a a a

    cbbaaa