void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(25, OUTPUT);
  pinMode(26, OUTPUT);
  pinMode(27, OUTPUT);
  pinMode(21, OUTPUT);
  pinMode(19, OUTPUT);
  pinMode(18, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(25, HIGH);
  digitalWrite(18, HIGH);
  delay(100);

  digitalWrite(25, LOW);
  digitalWrite(18, LOW);
  delay(100);

  digitalWrite(26, HIGH);
  digitalWrite(19, HIGH);
  delay(100);

  digitalWrite(26, LOW);
  digitalWrite(19,LOW);
  delay(100);

  digitalWrite(27, HIGH);
  digitalWrite(21, HIGH);
  delay(100);

  digitalWrite(27, LOW);
  digitalWrite(21, LOW);
  delay(100);

  delay(10);
}