#define LED_PIN 13
#define LED_PIN1 12
#define LED_PIN2 11
void setup() {
  pinMode(LED_PIN, OUTPUT);
  pinMode(LED_PIN1, OUTPUT);
  pinMode(LED_PIN2, OUTPUT);
}

void loop() {
 digitalWrite(LED_PIN, HIGH);
 delay(2000);
 digitalWrite(LED_PIN, LOW);
 delay(2000);

 digitalWrite(LED_PIN1, HIGH);
 delay(2000);
 digitalWrite(LED_PIN, LOW);
 delay(2000);

 digitalWrite(LED_PIN2, HIGH);
 delay(2000);
 digitalWrite(LED_PIN2, LOW);
 delay(2000);
}