int gruen = 11;
int rot = 10;
int gelb = 12;
int zeit = 1000;

void setup() {
  pinMode(rot, OUTPUT);
  pinMode(gruen, OUTPUT);
  pinMode(gelb, OUTPUT);
}

void loop() {
  digitalWrite(rot, HIGH);
  delay(zeit);
  digitalWrite(rot, LOW);
  digitalWrite(gelb, HIGH);
  delay(zeit);
  digitalWrite(gelb, LOW);
  digitalWrite(gruen, HIGH);
  delay(zeit);
  digitalWrite(gruen, LOW);
  delay(zeit);
  digitalWrite(gruen, HIGH);
  delay(zeit);
  digitalWrite(gruen, LOW);
  digitalWrite(gelb, HIGH);
  delay(zeit);
  digitalWrite(gelb, LOW);
  digitalWrite(rot, HIGH);
  delay(zeit);
  digitalWrite(rot, LOW);
  delay(zeit);
}