void setup() {
  // Traffic Light 1
  pinMode(0, OUTPUT); // Green
  pinMode(1, OUTPUT); // Yellow
  pinMode(2, OUTPUT); // Red

  // Traffic Light 2
  pinMode(3, OUTPUT); // Green
  pinMode(4, OUTPUT); // Yellow
  pinMode(5, OUTPUT); // Red

  // Traffic Light 3
  pinMode(6, OUTPUT); // Green
  pinMode(7, OUTPUT); // Yellow
  pinMode(8, OUTPUT); // Red
}

void loop() {
  // Traffic Light 1 Green, Traffic Light 2 Red, Traffic Light 3 Red
  digitalWrite(0, HIGH);  // Traffic Light 1 Green ON
  digitalWrite(1, LOW);   // Traffic Light 1 Yellow OFF
  digitalWrite(2, LOW);   // Traffic Light 1 Red OFF

  digitalWrite(3, LOW);   // Traffic Light 2 Green OFF
  digitalWrite(4, LOW);   // Traffic Light 2 Yellow OFF
  digitalWrite(5, HIGH);  // Traffic Light 2 Red ON

  digitalWrite(6, LOW);   // Traffic Light 3 Green OFF
  digitalWrite(7, LOW);   // Traffic Light 3 Yellow OFF
  digitalWrite(8, HIGH);  // Traffic Light 3 Red ON
  delay(5000);

  // Traffic Light 1 Yellow, Traffic Light 2 Red, Traffic Light 3 Red
  digitalWrite(0, LOW);   // Traffic Light 1 Green OFF
  digitalWrite(1, HIGH);  // Traffic Light 1 Yellow ON
  delay(2000);

  // Traffic Light 1 Red, Traffic Light 2 Green, Traffic Light 3 Red
  digitalWrite(1, LOW);   // Traffic Light 1 Yellow OFF
  digitalWrite(2, HIGH);  // Traffic Light 1 Red ON
  digitalWrite(3, HIGH);  // Traffic Light 2 Green ON
  digitalWrite(5, LOW);   // Traffic Light 2 Red OFF
  delay(5000);

  // Traffic Light 1 Red, Traffic Light 2 Yellow, Traffic Light 3 Red
  digitalWrite(3, LOW);   // Traffic Light 2 Green OFF
  digitalWrite(4, HIGH);  // Traffic Light 2 Yellow ON
  delay(2000);

  // Traffic Light 1 Red, Traffic Light 2 Red, Traffic Light 3 Green
  digitalWrite(4, LOW);   // Traffic Light 2 Yellow OFF
  digitalWrite(5, HIGH);  // Traffic Light 2 Red ON
  digitalWrite(6, HIGH);  // Traffic Light 3 Green ON
  digitalWrite(8, LOW);   // Traffic Light 3 Red OFF
  delay(5000);

  // Traffic Light 1 Red, Traffic Light 2 Red, Traffic Light 3 Yellow
  digitalWrite(6, LOW);   // Traffic Light 3 Green OFF
  digitalWrite(7, HIGH);  // Traffic Light 3 Yellow ON
  delay(2000);

  // Reset back to Traffic Light 1 Green
  digitalWrite(7, LOW);   // Traffic Light 3 Yellow OFF
  digitalWrite(8, HIGH);  // Traffic Light 3 Red ON
}