void setup() {
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, INPUT);
}

void loop() {
  digitalWrite(4,1);
  digitalWrite(3,0);
  digitalWrite(2,0);
  delay(2000);
  digitalWrite(4,1);
  digitalWrite(3,1);
  digitalWrite(2,0);
  delay(500);
  digitalWrite(4,0);
  digitalWrite(3,0);
  digitalWrite(2,1);
  delay(2000);
  for (int i = 0; i < 3; i++){
    digitalWrite(2,0);
    delay(500);
    digitalWrite(2,1);
    delay(500);
  }
  digitalWrite(4,0);
  digitalWrite(3,1);
  digitalWrite(2,0);
  delay(500);
}