int red=1; int yellow=3;int green=6;
void setup() {
  // put your setup code here, to run once:
pinMode(1,OUTPUT);
}

void loop() {
  digitalWrite(1,HIGH);
  delay(15000);
  digitalWrite(1,LOW);
  delay(15000);
  digitalWrite(3,HIGH);
  delay(15000);
  digitalWrite(3,LOW);
  delay(15000);
  digitalWrite(6,HIGH);
  delay(15000);
  digitalWrite(6,LOW);
  delay(15000);
  // put your main code here, to run repeatedly:

}