int GreenLED= 9;
int YellowLED = 8;
int RedLED = 10;
void setup() {
  // put your setup code here, to run once:
pinMode(GreenLED, OUTPUT);
pinMode(YellowLED, OUTPUT);
pinMode(RedLED, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(GreenLED, HIGH);
digitalWrite(YellowLED, LOW);
digitalWrite(RedLED, LOW);
delay(30000);
digitalWrite(GreenLED, LOW);
digitalWrite(YellowLED, HIGH);
digitalWrite(RedLED, LOW);
delay(3500);
digitalWrite(GreenLED, LOW);
digitalWrite(YellowLED, LOW);
digitalWrite(RedLED, HIGH);
delay(30000);
}