void setup() {
  pinMode(13, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(11, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(7, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(2, OUTPUT);
  pinMode(1, OUTPUT);
  pinMode(0, OUTPUT);
}

void loop() {
  digitalWrite(13, HIGH);
  digitalWrite(5, LOW);
  delay(50);
  digitalWrite(13, HIGH);
  digitalWrite(4, LOW);
  delay(50);
  digitalWrite(13, HIGH);
  digitalWrite(3, LOW);
  delay(50);
  digitalWrite(13, HIGH);
  digitalWrite(2, LOW);
  delay(50);
  digitalWrite(13, HIGH);
  digitalWrite(1, LOW);
  delay(50);
  digitalWrite(13, HIGH);
  digitalWrite(0, LOW);
  delay(50);
  digitalWrite(12, HIGH);
  digitalWrite(0, LOW);
  delay(50);
  digitalWrite(11, HIGH);
  digitalWrite(0, LOW);
  delay(50);
  digitalWrite(10, HIGH);
  digitalWrite(0, LOW);
  delay(50);
  digitalWrite(9, HIGH);
  digitalWrite(0, LOW);
  delay(50);
  digitalWrite(8, HIGH);
  digitalWrite(0, LOW);
  delay(50);
  digitalWrite(7, HIGH);
  digitalWrite(0, LOW);
  delay(50);
  digitalWrite(7, HIGH);
  digitalWrite(1, LOW);
  delay(50);
  digitalWrite(7, HIGH);
  digitalWrite(2, LOW);
  delay(50);
  digitalWrite(7, HIGH);
  digitalWrite(3, LOW);
  delay(50);
  digitalWrite(7, HIGH);
  digitalWrite(4, LOW);
  delay(50);
  digitalWrite(7, HIGH);
  digitalWrite(5, LOW);
  delay(50);
  digitalWrite(8, HIGH);
  digitalWrite(5, LOW);
  delay(50);
  digitalWrite(9, HIGH);
  digitalWrite(5, LOW);
  delay(50);
  digitalWrite(10, HIGH);
  digitalWrite(5, LOW);
  delay(50);
  digitalWrite(11, HIGH);
  digitalWrite(5, LOW);
  delay(50);
  digitalWrite(12, HIGH);
  digitalWrite(5, LOW);
  delay(50);
  digitalWrite(12, HIGH);
  digitalWrite(4, LOW);
  delay(50);
  digitalWrite(12, HIGH);
  digitalWrite(3, LOW);
  delay(50);
  digitalWrite(12, HIGH);
  digitalWrite(2, LOW);
  delay(50);
  digitalWrite(12, HIGH);
  digitalWrite(1, LOW);
  delay(50);
  digitalWrite(11, HIGH);
  digitalWrite(1, LOW);
  delay(50);
  digitalWrite(10, HIGH);
  digitalWrite(1, LOW);
  delay(50);
  digitalWrite(9, HIGH);
  digitalWrite(1, LOW);
  delay(50);
  digitalWrite(8, HIGH);
  digitalWrite(1, LOW);
  delay(50);
  digitalWrite(8, HIGH);
  digitalWrite(2, LOW);
  delay(50);
  digitalWrite(8, HIGH);
  digitalWrite(3, LOW);
  delay(50);
  digitalWrite(8, HIGH);
  digitalWrite(4, LOW);
  delay(50);
  digitalWrite(9, HIGH);
  digitalWrite(4, LOW);
  delay(50);
  digitalWrite(10, HIGH);
  digitalWrite(4, LOW);
  delay(50);
  digitalWrite(11, HIGH);
  digitalWrite(4, LOW);
  delay(50);
  digitalWrite(11, HIGH);
  digitalWrite(3, LOW);
  delay(50);
  digitalWrite(11, HIGH);
  digitalWrite(2, LOW);
  delay(50);
  digitalWrite(10, HIGH);
  digitalWrite(2, LOW);
  delay(50);
  digitalWrite(9, HIGH);
  digitalWrite(2, LOW);
  delay(50);
  digitalWrite(9, HIGH);
  digitalWrite(3, LOW);
  delay(50);
  digitalWrite(10, HIGH);
  digitalWrite(3, LOW);
  delay(50);
}