Introduction
I have used Swift for windows 1.9 for debugging purpose. But you can use any Swift programming language compiler as per your availability.
func checknumbers(_ input: [Int]) -> Bool { for (index, number) in input.enumerated() { let thirdIndex = index + 2 let secondIndex = index + 1 if secondIndex < input.endIndex && number == input[secondIndex] && number == input[thirdIndex] { return true } } return false } print(checknumbers([10, 10, 30, 30, 10])) print(checknumbers([10, 10, 10, 20, 20, 20, 20])) print(checknumbers([10, 10, 10, 20, 20]))
Result