int buttonState=0; 
int buttonPin=2; 
int stopSign=13; 
int slowSign=12;
int goSign=11;

void setup() {
  pinMode(buttonPin, INPUT);
  pinMode(stopSign, OUTPUT);
  pinMode(slowSign, OUTPUT);
  pinMode(goSign, OUTPUT);
}

void loop () {
  buttonState=digitalRead(buttonPin);
  if (buttonState==HIGH) {
    digitalWrite(goSign, LOW);
    digitalWrite(slowSign, HIGH);
    delay(5000);
    digitalWrite(slowSign, LOW);
    digitalWrite(stopSign, HIGH);
    delay (10000);
    digitalWrite(stopSign, LOW);
  } else {
    digitalWrite(goSign, HIGH);
  }
  delay(30);
}