Advent of Code 2024

[tevelee (Laszlo Teveli)]

Ben’s memoization helper proved invaluable for Day 11. My solution.

@Ben_Cohen

func memoize<In: Hashable, Out>(_ f: @escaping (In) -> Out) -> (In) -> Out {
  var memo: [In: Out] = [:]
  return {
    if let result = memo[$0] {
      return result
    } else {
      let result = f($0)
      memo[$0] = result
      return result
    }
  }
}