int redLed = 12;    // pin for red LED
int yellowLed = 8;  // pin for yellow LED
int greenLed = 7;   // pin for green LED
int switchPin = 2;  // pin for the switch
int buttonState;    // variable to store the button state

void setup() {
  pinMode(redLed, OUTPUT);
  pinMode(yellowLed, OUTPUT);
  pinMode(greenLed, OUTPUT);
  pinMode(switchPin, INPUT_PULLUP); // Use internal pull-up resistor
}

void loop() {
  buttonState = digitalRead(switchPin);

  if (buttonState == HIGH) { // Button not pressed
    digitalWrite(redLed, HIGH);
    digitalWrite(yellowLed, LOW);
    digitalWrite(greenLed, LOW);
    delay(5000); // Wait 5 seconds
  } else { // Button pressed
    digitalWrite(redLed, LOW);
    digitalWrite(yellowLed, HIGH);
    digitalWrite(greenLed, LOW);
    delay(5000);

    digitalWrite(yellowLed, LOW);
    digitalWrite(greenLed, HIGH);
    delay(5000);
  }
}