#define LED_1 4
#define LED_2 16
#define LED_3 17

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  pinMode(LED_1, OUTPUT);
  pinMode(LED_2, OUTPUT);
  pinMode(LED_3, OUTPUT);
}

void loop() {

  for( int i = 0; i < 8; i++ ){
    if ( i == 0 ){
      delay(500);

      digitalWrite(LED_1, LOW);
      digitalWrite(LED_2, LOW);
      digitalWrite(LED_3, LOW);
    }

    if ( i == 1 ){
      digitalWrite(LED_1, LOW);
      digitalWrite(LED_2, LOW);
      digitalWrite(LED_3, HIGH);

      delay(500);
    }
    
    if ( i == 2 ){
      digitalWrite(LED_1, LOW);
      digitalWrite(LED_2, HIGH);
      digitalWrite(LED_3, LOW);

      delay(500);
    }    
    
    if ( i == 3 ){
      digitalWrite(LED_1, LOW);
      digitalWrite(LED_2, HIGH);
      digitalWrite(LED_3, HIGH);

      delay(500);
    }

    if ( i == 4 ){
      digitalWrite(LED_1, HIGH);
      digitalWrite(LED_2, LOW);
      digitalWrite(LED_3, LOW);

      delay(500);
    }    
    
    if ( i == 5 ){
      digitalWrite(LED_1, HIGH);
      digitalWrite(LED_2, LOW);
      digitalWrite(LED_3, HIGH);

      delay(500);
    }    
    
    if ( i == 6 ){
      digitalWrite(LED_1, LOW);
      digitalWrite(LED_2, HIGH);
      digitalWrite(LED_3, HIGH);

      delay(500);
    }
    
    if ( i == 7 ){
      digitalWrite(LED_1, LOW);
      digitalWrite(LED_2, HIGH);
      digitalWrite(LED_3, HIGH);

      delay(500);
    }
  }

}