const int pin_red_L12 = 13;
const int pin_yellow_L12 = 12;
const int pin_green_L12 = 11;

const int pin_red_L3 = 10;
const int pin_yellow_L3 = 9;
const int pin_green_L3 = 8;

enum State_t {
  all_red_1, yellow_L12, green_L12, yellow_L12_end,
  all_red_2, yellow_L3, green_L3, yellow_L3_end
};

State_t curr_state;

void setup() {
  pinMode(pin_red_L12, OUTPUT);
  pinMode(pin_yellow_L12, OUTPUT);
  pinMode(pin_green_L12, OUTPUT);
  pinMode(pin_red_L3, OUTPUT);
  pinMode(pin_yellow_L3, OUTPUT);
  pinMode(pin_green_L3, OUTPUT);

  curr_state = all_red_1;
}

void loop() {
  switch (curr_state) {
    case all_red_1:
      setLights(HIGH, LOW, LOW, HIGH, LOW, LOW);
      delay(5000);
      curr_state = yellow_L12;
      break;

    case yellow_L12:
      setLights(LOW, HIGH, LOW, HIGH, LOW, LOW);
      delay(1000);
      curr_state = green_L12;
      break;

    case green_L12:
      setLights(LOW, LOW, HIGH, HIGH, LOW, LOW);
      delay(5000);
      curr_state = yellow_L12_end;
      break;

    case yellow_L12_end:
      setLights(LOW, HIGH, LOW, HIGH, LOW, LOW);
      delay(1000);
      curr_state = all_red_2;
      break;

    case all_red_2:
      setLights(HIGH, LOW, LOW, HIGH, LOW, LOW);
      delay(5000);
      curr_state = yellow_L3;
      break;

    case yellow_L3:
      setLights(HIGH, LOW, LOW, LOW, HIGH, LOW);
      delay(1000);
      curr_state = green_L3;
      break;

    case green_L3:
      setLights(HIGH, LOW, LOW, LOW, LOW, HIGH);
      delay(5000);
      curr_state = yellow_L3_end;
      break;

    case yellow_L3_end:
      setLights(HIGH, LOW, LOW, LOW, HIGH, LOW);
      delay(1000);
      curr_state = all_red_1;
      break;
  }
}

void setLights(bool r12, bool y12, bool g12, bool r3, bool y3, bool g3) {
  digitalWrite(pin_red_L12, r12);
  digitalWrite(pin_yellow_L12, y12);
  digitalWrite(pin_green_L12, g12);

  digitalWrite(pin_red_L3, r3);
  digitalWrite(pin_yellow_L3, y3);
  digitalWrite(pin_green_L3, g3);
}