int leds[13];
int startPin = 0;

void setup() {
  for (int i = 0; i < 13; i++) {
    leds[i] = i;
    pinMode(leds[i], OUTPUT);
  }
  
}

void loop() {
  for (int i = startPin; i < 13; i++) {
      digitalWrite(leds[i], HIGH);
    delay(20);
  }
  
   for (int i = 0; i < startPin; i++) {
     digitalWrite(leds[i], HIGH);
     delay(20);
   }
     
  for (int i = startPin; i >= 0; i--) {
    digitalWrite(leds[i], LOW);
    delay(10);
  }
   for (int i = 13; i > startPin; i--) {
    digitalWrite(leds[i], LOW);
    delay(10);
  }
  delay(200);
  startPin++;
  checkStartPin();
  
}
void checkStartPin() {
  if (startPin > 12) {
    startPin = 0;
  }
  if (startPin == 0) {
    for (int i = 0; i < 13; i++) {
      digitalWrite(leds[i], HIGH);
      delay(40);
    }
    for (int i = 0; i < 13; i++) {
      digitalWrite(leds[i], LOW);
      delay(40);
    }
  
  
    for (int i = 0; i < 13; i++) {
      digitalWrite(leds[i], HIGH);
      delay(30);
    }
    for (int i = 0; i < 13; i++) {
      digitalWrite(leds[i], LOW);
      delay(30);
    }
    
    for (int i = 0; i < 13; i++) {
      digitalWrite(leds[i], HIGH);
      delay(20);
    }
    for (int i = 0; i < 13; i++) {
      digitalWrite(leds[i], LOW);
      delay(20);
    }
    delay(150);
    
    offBlink();
    delay(100);
    
    offBlink();
    delay(100);
    
    offBlink();
    delay(100);
    
    
    for (int i = 0; i < 13; i++) {
      digitalWrite(leds[i], HIGH);
    }
    delay(500);
    for (int i = 0; i < 13; i++) {
      digitalWrite(leds[i], LOW);
    }
    delay(300);
    
    
  }
}

void offBlink() {
  for (int i = 0; i < 13; i++) {
      if (i != 0) {
        if (i % 2 == 0) {
          digitalWrite(leds[i], HIGH);
          delay(10);
        }
      }
    }
     for (int i = 0; i < 13; i++) {
      if (i != 0) {
        if (i % 2 != 0) {
          digitalWrite(leds[i], HIGH);
          delay(10);
        }
      }
    }
    
    for (int i = 0; i < 13; i++) {
      if (i != 0) {
        if (i % 2 == 0) {
          digitalWrite(leds[i], LOW);
          delay(10);
        }
      }
    }
    for (int i = 0; i < 13; i++) {
      if (i != 0) {
        if (i % 2 != 0) {
          digitalWrite(leds[i], LOW);
          delay(10);
        }
      }
    }
}