#define GREEN 3
#define YELOW 5
#define RED 6

void setup() {
  // put your setup code here, to run once:
  pinMode(GREEN, OUTPUT);
  digitalWrite(GREEN, LOW);

  pinMode(YELOW, OUTPUT);
  digitalWrite(YELOW, LOW);

  pinMode(RED, OUTPUT);
  digitalWrite(RED, LOW);

}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(GREEN, HIGH);
  delay(100);
  digitalWrite(GREEN, LOW);
  delay(100);

  digitalWrite(YELOW, HIGH);
  delay(100);
  digitalWrite(YELOW, LOW);
  delay(100);

  digitalWrite(RED, HIGH);
  delay(100);
  digitalWrite(RED, LOW);
  delay(100);


}