// กำหนดขาของ LED 6 ดวง
int ledPins[] = {2, 3, 4, 5, 6, 7};

class Led {
  private:
    int pin;

  public:
    Led(int p) : pin(p) {
      pinMode(pin, OUTPUT);
    }

    void stateOn() {
      digitalWrite(pin, HIGH);
    }

    void stateOff() {
      digitalWrite(pin, LOW);
    }
};

class Button {
  private:
    int pin;
    int lastState;
    int currentState;

  public:
    Button(int p) : pin(p), lastState(LOW), currentState(LOW) {
      pinMode(pin, INPUT_PULLUP);
    }

    void update() {
      lastState = currentState;
      currentState = digitalRead(pin);
    }

    bool isPressed() {
      return currentState == LOW;
    }

    int getState() {
      return currentState;
    }
};

class Controlled {
  private:
    Led* leds[6];
    int currentLed;

  public:
    Controlled() : currentLed(0) {
      for (int i = 0; i < 6; i++) {
        leds[i] = new Led(ledPins[i]);
      }
    }

    void stateUp() {
      if (currentLed < 3) {
        leds[currentLed]->stateOn();
        currentLed++;
      }
    }

    void stateDown() {
      for (int i = 0; i < 6; i++) {
        leds[i]->stateOff();
      }
      currentLed = 0;
    }
};

Controlled controller;

void setup() {
  // ไม่ต้องทำอะไรใน setup
}

void loop() {
  controller.stateUp();
  delay(500);
  controller.stateDown();
  delay(500);
}