The overhead for iterative deepening with b − 1 on the denominator

(page 99) is not a good approximation when b ≈ 1. Give a better estimate of the complexity of iterative deepening when b ≈ 1. [Hint: Think about the case when b = 1.] How does this compare with A∗ for such graphs? Suggest a way that iterative deepening can have a lower overhead when the branching factor is close to 1.