범위연산 (range operators) 활용

1. 기본




2. 배열

let numbers = [10, 20, 30, 40, 50]

let part1 = numbers[0 ..< 5]

let part2 = numbers[2...]

let part3 = numbers[..<4]

let part4 = numbers[0...3]

print("part1 = \(part1)")

print("part2 = \(part2)")

print("part3 = \(part3)")

print("part4 = \(part4)")

part1 = [10, 20, 30, 40, 50]

part2 = [30, 40, 50]

part3 = [10, 20, 30, 40]

part4 = [10, 20, 30, 40]

3. Int Array 만들기

1)

let day = [Int](1...31)

print("15 is ", day.contains(15))

print("40 is ", day.contains(40))

print(day)

15 is  true

40 is  false

[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31]

2)

let lessThanFive = 0.0..<5.0

print(lessThanFive.contains(3.14))  // Prints "true"

print(lessThanFive.contains(5.0))   // Prints "false"

4. 스트링

let text = "Hello World!"

if let firstSpace = text.index(of: " ") {

    print(text[text.startIndex..<text.endIndex])

    

    print("-----------")

    print(text[text.startIndex...])

    print(text[..<firstSpace])

    

    print("-----------")

    print(text[text.startIndex...firstSpace])

    

    let nextIndex = text.index(firstSpace, offsetBy: 1)

    print(text[text.startIndex...nextIndex])

}

Hello World!

-----------

Hello World!

Hello

-----------

Hello 

Hello W