// Define LED pins
int led1 = 2;   // Red LED
int led2 = 3;   // Yellow LED
int led3 = 4;   // Green LED

void setup() {
  Serial.begin(9600);   // Start serial monitor

  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
}

void loop() {
  // 🔴 LED 1 ON
  Serial.println("RED LED ON");
  digitalWrite(led1, HIGH);
  delay(500);
  digitalWrite(led1, LOW);

  // 🟡 LED 2 ON
  Serial.println("YELLOW LED ON");
  digitalWrite(led2, HIGH);
  delay(500);
  digitalWrite(led2, LOW);

  // 🟢 LED 3 ON
  Serial.println("GREEN LED ON");
  digitalWrite(led3, HIGH);
  delay(500);
  digitalWrite(led3, LOW);

  Serial.println("Cycle Complete\n");
}