int Led1=5;
int Led2=4;
int Led3=3;

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

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(Led1, HIGH);
  delay(300);
  digitalWrite(Led1, LOW);
  delay(300);
  
  digitalWrite(Led2, HIGH);
  delay(300);
  digitalWrite(Led2, LOW);
  delay(300);
  
  digitalWrite(Led3, HIGH);
  delay(300);
  digitalWrite(Led3, LOW);
  delay(300);

}