void setup(){
  pinMode(23, OUTPUT);
  pinMode(22, OUTPUT);
  pinMode(21, OUTPUT);
  pinMode(19, OUTPUT);
  pinMode(18, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(17, OUTPUT);
  pinMode(16, OUTPUT);
  pinMode(4 , OUTPUT);
  pinMode(0, OUTPUT);
  pinMode(2, OUTPUT);
  pinMode(15, OUTPUT);
}

void loop(){
  digitalWrite(23,HIGH);
  delay(1000);
  digitalWrite(23, LOW);
  delay(1000);
  digitalWrite(22,HIGH);
  delay(1000);
  digitalWrite(22, LOW);
  delay(1000);
  digitalWrite(21,HIGH);
  delay(1000);
  digitalWrite(21, LOW);
  delay(1000);
  digitalWrite(19,HIGH);
  delay(1000);
  digitalWrite(19, LOW);
  delay(1000);
  digitalWrite(18,HIGH);
  delay(1000);
  digitalWrite(18, LOW);
  delay(1000);
  digitalWrite(5,HIGH);
  delay(1000);
  digitalWrite(5, LOW);
  delay(1000);
  digitalWrite(17,HIGH);
  delay(1000);
  digitalWrite(17, LOW);
  delay(1000);
  digitalWrite(16,HIGH);
  delay(1000);
  digitalWrite(16, LOW);
  delay(1000);
  digitalWrite(4,HIGH);
  delay(1000);
  digitalWrite(4, LOW);
  delay(1000);
  digitalWrite(0,HIGH);
  delay(1000);
  digitalWrite(0, LOW);
  delay(1000);
  digitalWrite(2,HIGH);
  delay(1000);
  digitalWrite(2, LOW);
  delay(1000);
  digitalWrite(15,HIGH);
  delay(1000);
  digitalWrite(15, LOW);
  delay(1000);
}