int redled = 9;
int yellowled = 10;
int greenled = 11;

void setup() {
  pinMode(redled, OUTPUT);
  pinMode(yellowled, OUTPUT);
  pinMode(greenled, OUTPUT);
}

void loop() {
  // Hijau
  digitalWrite(greenled, HIGH);
  delay(5000);
  digitalWrite(greenled, LOW);

  // Kuning
  digitalWrite(yellowled, HIGH);
  delay(2000);
  digitalWrite(yellowled, LOW);

  // Merah
  digitalWrite(redled, HIGH);
  delay(5000);
  digitalWrite(redled, LOW);
}