enum Weather {
    case sunny
    case cloudy
    case rainy
}

// 사용자로부터 입력 받기
print("What is the weather today? (sunny/cloudy/rainy)")
if let userInput = readLine() {
    // 입력된 값이 열거형 케이스와 일치하는지 확인
    let userWeather: Weather?
    switch userInput {
    case "sunny":
        userWeather = .sunny
    case "cloudy":
        userWeather = .cloudy
    case "rainy":
        userWeather = .rainy
    default:
        userWeather = nil
    }
    
    if let weather = userWeather {
        print("The weather today is \(weather)!")
    } else {
        print("Invalid input!")
    }
}