void setup() {
  // variables y pines
  pinMode(5, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(3, OUTPUT);
}
void loop() {
  // codificacion - acciones
  digitalWrite(5, HIGH);  
  delay(1000);
  digitalWrite(5, LOW);
  delay(1000);

  digitalWrite(4, HIGH);  
  delay(1000);
  digitalWrite(4, LOW);
  delay(1000);
  
  digitalWrite(3, HIGH);  
  delay(1000);
  digitalWrite(3, LOW);
  delay(1000);
}