Here is one possible best solution for the second sample. Claim Conjecture 1 firstly and others consequently following the instructions.
Conjecture 1: The number of 1 in B is odd. If true, go to Conjecture 2, else go to Conjecture 3.
Conjecture 2: The length of B is 1. If true, B is [1], else go to Conjecture 4.
Conjecture 3: The first element of B is 1. If true, go to Conjecture 5, else go to Conjecture 6.
Conjecture 4: The length of B is 4. If true, B is [1, 2, 1, 1], else go to Conjecture 7.
Conjecture 5: The length of B is 3. If true, B is [1, 2, 1], else B is [1, 1].
Conjecture 6: The length of B is 1. If true, B is [2], else B is [2, 1, 1].
Conjecture 7: The first element of B is 1. If true, B is [1, 2], else B is [2, 1].