int r1 = 2, y1 = 3, g1 = 4,
     r2 = 5, y2 = 6, g2 = 7,
     r3 = 8, y3 = 9, g3 = 10,
     r4 = 11, y4 = 12, g4 = 13;

void setup() {
  // put your setup code here, to run once:
  pinMode(r1, OUTPUT);
  pinMode(g1, OUTPUT);
  pinMode(g1, OUTPUT);
  pinMode(r2, OUTPUT);
  pinMode(y2, OUTPUT);
  pinMode(g2, OUTPUT);
  pinMode(r3, OUTPUT);
  pinMode(y3, OUTPUT);
  pinMode(g3, OUTPUT);
  pinMode(r4, OUTPUT);
  pinMode(y4, OUTPUT);
  pinMode(g4, OUTPUT);

}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(r2, HIGH);
  digitalWrite(r3, HIGH);
  digitalWrite(r4, HIGH);
  digitalWrite(y1, HIGH);
  delay(500);
  digitalWrite(y1, LOW);
  digitalWrite(g1, HIGH);
  delay(1000);
  digitalWrite(g1, LOW);
  digitalWrite(y1, HIGH);
  delay(500);
  digitalWrite(y1, LOW);
  digitalWrite(r1, HIGH);
  digitalWrite(r2, LOW);
  digitalWrite(y2, HIGH);
  delay(500);
  digitalWrite(y2, LOW);
  digitalWrite(g2, HIGH);
  delay(1000);
  digitalWrite(g2, LOW);
  digitalWrite(y2, HIGH);
  delay(500);
  digitalWrite(y2, LOW);
  digitalWrite(r2, HIGH);
  digitalWrite(r3, LOW);
  digitalWrite(y3, HIGH);
  delay(500);
  digitalWrite(y3, LOW);
  digitalWrite(g3, HIGH);
  delay(1000);
  digitalWrite(g3, LOW);
  digitalWrite(y3, HIGH);
  delay(500);
  digitalWrite(y3, LOW);
  digitalWrite(r3, HIGH);
  digitalWrite(r4, LOW);
  digitalWrite(y4, HIGH);
  delay(500);
  digitalWrite(y4, LOW);
  digitalWrite(g4, HIGH);
  delay(1000);
  digitalWrite(g4, LOW);
  digitalWrite(y4, HIGH);
  delay(500);
  digitalWrite(y4, LOW);
  digitalWrite(r4, HIGH);
  digitalWrite(r1, LOW);

}