for in let platforms = ["iOS", "macOS", "tvOS", "watchOS"] for os in platforms { print("Swift works great on \(os).") } Swift works great on iOS. Swift works great on macOS. Swift works great on tvOS. Swift works great on watchOS. // 5를 포함 for i in 1...5 { print("Counting from 1 through 5: \(i)") } // 5를 미포함 for i in 1..