#define Led 2
#define Led2 15
#define Led1 4
#define Led3 12

void setup() {
  // put your setup code here, to run once:
  pinMode(Led, OUTPUT);
    pinMode(Led2, OUTPUT);
     pinMode(Led3, OUTPUT);
  pinMode(Led1, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(Led, HIGH);
  delay(500); // this speeds up the simulation
  digitalWrite(Led, LOW);
  delay(500);
   digitalWrite(Led2, HIGH);
  delay(500); // this speeds up the simulation
  digitalWrite(Led2, LOW);
  delay(500);
  digitalWrite(Led1, HIGH);
  delay(500); // this speeds up the simulation
  digitalWrite(Led1, LOW);
  delay(500);
  digitalWrite(Led3, HIGH);
  delay(500); // this speeds up the simulation
  digitalWrite(Led3, LOW);
  delay(500);
}