LinearSearch.swift

func linearSearch<T: Equatable>(_ array: [T], _ object: T) -> Int? {
  for (index, obj) in array.enumerated() where obj == object {
    return index
  }
  return nil
}

func linearSearch1<T: Equatable>(_ array: [T], _ object: T) -> Array<T>.Index? {
    return array.index { $0 == object }
}