int s[] = {15, 2, 4, 5, 18, 21, 19, 22};

void setup() {
  
  
  pinMode(s[5], OUTPUT);
  pinMode(s[6], OUTPUT);
  pinMode(s[1], OUTPUT);
  pinMode(s[2], OUTPUT);
}

void loop() {
  
  
  digitalWrite(s[5], HIGH);
  digitalWrite(s[6], HIGH);
  digitalWrite(s[1], HIGH);
  digitalWrite(s[2], HIGH);
  delay(10);
}