void setup() {
  pinMode(13, OUTPUT); // Set pin 13 as an output
  pinMode(12, OUTPUT); // Set pin 12 as an output
  pinMode(8, OUTPUT);  // Set pin 8 as an output
}

void loop() {
  digitalWrite(13, HIGH); // Turn ON LED connected to pin 13
  delay(500); // Wait for 500 milliseconds
  digitalWrite(13, LOW); // Turn OFF LED connected to pin 13
  delay(500); // Wait for 500 milliseconds

  digitalWrite(12, HIGH); // Turn ON LED connected to pin 12
  delay(500); // Wait for 500 milliseconds
  digitalWrite(12, LOW); // Turn OFF LED connected to pin 12
  delay(500); // Wait for 500 milliseconds

  digitalWrite(8, HIGH); // Turn ON LED connected to pin 8
  delay(500); // Wait for 500 milliseconds
  digitalWrite(8, LOW); // Turn OFF LED connected to pin 8
  delay(500); // Wait for 500 milliseconds
}