void setup()
{
  // put your setup code here, to run once:
  Serial.begin(115200);
  // traffic light 1
  pinMode(27, OUTPUT);
  pinMode(14, OUTPUT);
  pinMode(12, OUTPUT);
  //Traffic light 2
  pinMode(21, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
}


void loop()
{
  digitalWrite(27,HIGH);
  digitalWrite(4,HIGH);
  delay(1000);


  digitalWrite(27,LOW);
  digitalWrite(4, LOW);
  delay(1000);
 
   digitalWrite(14, HIGH);
  digitalWrite(5, HIGH);
  delay(1000);
 
  digitalWrite(14, LOW);
  digitalWrite(5, LOW);
  delay(1000);


  digitalWrite(12, HIGH);
  digitalWrite(21, HIGH);
  delay(1000);


  digitalWrite(12, LOW);
  digitalWrite(21, LOW);
  delay(1000);

}