Coin Sequence Probability | Dataford Interview Questions

What is the probability of getting a specific sequence of heads and tails versus another when tossing a fair coin multiple times?

Implement sequence_probabilities(sequence_a, sequence_b). Each sequence is a string containing only H and T; return a two-element list containing the probability of each exact sequence. An exact sequence of length n has probability 1 / 2^n, regardless of its order.

Input and Output

Input: two non-empty strings, sequence_a and sequence_b.
Output: [probability_a, probability_b] as floating-point values.

Constraints

1 <= len(sequence_a), len(sequence_b) <= 100
Each sequence contains only the characters 'H' and 'T'
The coin is fair and tosses are independent

Function Signature

def sequence_probabilities(sequence_a, sequence_b):

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