1. Replace the ??? in the random stream definition  below
   with the proper weight according to the following probability table:

         A   B   C   D
        .2  .1  .3  .4

   (items (A weight ???)
          (B weight ???)
          (C weight ???)
          (D weight ???)
          in random)


2. Implement a rhythm stream that produces the following 1st order markov

                   Current:
                    Q    E   16
                Q  .2    0.0  1.0
        Next:   E  .4   .25  0.0
               16  .4   .75  0.0


3. Write a graph stream that implements 1st order Morkov of Happy Birthday:

   (notes g3 g a g c4 b3   g g a g d4 c   g3 g g4 e c b3 a   f4 f e c d c)

      G3     A3     B3     C4     D4     E4     F4     G4     
G3    0.375, 0.250, 0.000, 0.125, 0.125, 0.000, 0.000, 0.125
A3    0.667, 0.000, 0.000, 0.000, 0.000, 0.000, 0.333, 0.000
B3    0.500, 0.500, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000
C4    0.400, 0.000, 0.400, 0.000, 0.200, 0.000, 0.000, 0.000
D4    0.000, 0.000, 0.000, 1.000, 0.000, 0.000, 0.000, 0.000
E4    0.000, 0.000, 0.000, 1.000, 0.000, 0.000, 0.000, 0.000
F4    0.000, 0.000, 0.000, 0.000, 0.000, 0.500, 0.500, 0.000
G4    0.000, 0.000, 0.000, 0.000, 0.000, 1.000, 0.000, 0.000

      1  2  3  4  5  6  7  8
      G3 A3 B3 C4 D4 E4 F4 G4     
G3    3, 2, 0, 1, 1, 0, 0, 1
A3    2, 0, 0, 0, 0, 0, 1, 0
B3    1, 1, 0, 0, 0, 0, 0, 0
C4    2, 0, 2, 0, 1, 0, 0, 0
D4    0, 0, 0, 1, 0, 0, 0, 0
E4    0, 0, 0, 1, 0, 0, 0, 0
F4    0, 0, 0, 0, 0, 1, 1, 0
G4    0, 0, 0, 0, 0, 1, 0, 0


4. Compose a chant melodic pattern that "prefers" the middle notes, ie the
   probability of notes moving toward either end gets harder as 
   the notes range to the extreems.

5. Implement a different melody using a random walks containing at least
   6 nodes. The middle node must contain a subpattern, not a single note.
   The topmost node (last node in graph) picks the next one down 100% of the 
   time, the lowest node (first node in the graph) picks either of the two
   nodes closest to it.

6. Make a larger pattern the plays a cycle of the graph from #3
   for 8, 10 or 12 notes followed by a rest.