const int LED_PINS[] = {2, 3, 4, 5, 6, 7, 8, 9};
void setup() {
for(int i=0; i<=8; i++){
 pinMode(LED_PINS[i], OUTPUT);

}

  /*pinMode(LED_PINS[0], OUTPUT);
  pinMode(LED_PINS[1], OUTPUT);
  pinMode(LED_PINS[2], OUTPUT);
  pinMode(LED_PINS[3], OUTPUT);
  pinMode(LED_PINS[4], OUTPUT);
  pinMode(LED_PINS[5], OUTPUT);
  pinMode(LED_PINS[6], OUTPUT);
  pinMode(LED_PINS[7], OUTPUT);*/
}

void loop() {
for(int i=0; i<=8; i++){
  digitalWrite(LED_PINS[i], HIGH);
  delay(100);
  digitalWrite(LED_PINS[i], LOW);
}

  /*digitalWrite(LED_PINS[0], HIGH);
  delay(100);
  digitalWrite(LED_PINS[0], LOW);

  digitalWrite(LED_PINS[1], HIGH);
  delay(100);
  digitalWrite(LED_PINS[1], LOW);

  digitalWrite(LED_PINS[2], HIGH);
  delay(100);
  digitalWrite(LED_PINS[2], LOW);

  digitalWrite(LED_PINS[3], HIGH);
  delay(100);
  digitalWrite(LED_PINS[3], LOW);

  digitalWrite(LED_PINS[4], HIGH);
  delay(100);
  digitalWrite(LED_PINS[4], LOW);

  digitalWrite(LED_PINS[5], HIGH);
  delay(100);
  digitalWrite(LED_PINS[5], LOW);

  digitalWrite(LED_PINS[6], HIGH);
  delay(100);
  digitalWrite(LED_PINS[6], LOW);

  digitalWrite(LED_PINS[7], HIGH);
  delay(100);
  digitalWrite(LED_PINS[7], LOW);*/

}