void setup() {
  pinMode(23, INPUT);
  pinMode(27, OUTPUT);
  pinMode(22, INPUT);
  pinMode(26, OUTPUT);
  pinMode(21, INPUT);
  pinMode(25, OUTPUT);
}

void loop() {
  if(digitalRead(23)==LOW)
  digitalWrite(27,HIGH);
  else
  digitalWrite(27, LOW);
  if(digitalRead(23)==LOW)
  digitalWrite(26,HIGH);
  else
  digitalWrite(26, LOW);
  if(digitalRead(23)==LOW)
  digitalWrite(25,HIGH);
  else
  digitalWrite(25, LOW);
  if(digitalRead(23)==LOW)
  digitalWrite(26,HIGH);
  else
  digitalWrite(26, LOW);
  if (digitalRead(21) == LOW) {
    digitalWrite(25, HIGH);
    delay(1000);
    digitalWrite(25, LOW);
    digitalWrite(26, HIGH);
    delay(1000);
    digitalWrite(26, LOW);
    digitalWrite(27, HIGH);
    delay(1000);
    digitalWrite(27, LOW);


  } 
  else {
    digitalWrite(25, LOW);
    digitalWrite(26, LOW);
    digitalWrite(27, LOW);
  }

  if (digitalRead(22) == LOW) {
    digitalWrite(27, HIGH);
    delay(1000);
    digitalWrite(27, LOW);
    digitalWrite(26, HIGH);
    delay(1000);
    digitalWrite(26, LOW);
    digitalWrite(25, HIGH);
    delay(1000);
    digitalWrite(25, LOW);


  } 
  else {
    digitalWrite(27, LOW);
    digitalWrite(26, LOW);
    digitalWrite(25, LOW);
  }
}