def binomial_coeff(n: int, k: int) -> int:
    """Compute the binomial coefficient 'n choose k'.
    
    n: number of trials
    k: number of successes
    """

    return 1 if k == 0 else 0 if n == 0 else (binomial_coeff(n - 1, k) + binomial_coeff(n - 1, k - 1))