void setup() {
  Serial.begin(9600);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, INPUT);  // Use pin 7 for the pedestrian button
  pinMode(13, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(11, OUTPUT);
}

void loop() {
  // Highway 1 green, Highway 2 red
  digitalWrite(4, HIGH);
  digitalWrite(12, HIGH);
  delay(5000);
  
  // Prepare for traffic light change
  digitalWrite(6, HIGH);
  delay(1000);
  digitalWrite(4, LOW);
  digitalWrite(5, LOW);

  // Highway 1 green, Highway 2 red
  digitalWrite(4, HIGH);
  digitalWrite(12, HIGH);
  delay(5000);

  // Prepare for traffic light change
  digitalWrite(11, HIGH);
  delay(1000);
  digitalWrite(12, LOW);
  digitalWrite(13, LOW);

  // Pedestrian crossing sequence if the button is pressed
  if (digitalRead(7) == HIGH) {
    pedestrianCrossing();
  }
}

void pedestrianCrossing() {
  // Stop both highways
  digitalWrite(5, HIGH);
  digitalWrite(12, HIGH);

  // Pedestrian signal
  for (int i = 0; i < 3; i++) {
    digitalWrite(6, HIGH);
    digitalWrite(11, HIGH);
    delay(500);
  }

  digitalWrite(6, LOW);
  digitalWrite(11, LOW);
  delay(500);

  // Allow pedestrian to cross
  digitalWrite(4, HIGH);
  digitalWrite(13, HIGH);
  delay(5000);

  // Prepare for traffic light change
  digitalWrite(4, LOW);
  digitalWrite(13, LOW);

  // Resume Normal traffic sequence
  digitalWrite(5, LOW);
  digitalWrite(6, HIGH);
  delay(1000);
  digitalWrite(6, LOW);
}