/* Constants - define pin numbers for LEDs,
   buttons and speaker, and also the game tones: */
const uint8_t ledPins[] = {9, 10, 11, 12};
const uint8_t buttonPins[] = {2, 3, 4, 5};
int score = 0;
int timer = 30;
bool playing = false;

void setup() {
  Serial.begin(9600);
  for (byte i = 0; i < 4; i++) {
    pinMode(ledPins[i], OUTPUT);
    pinMode(buttonPins[i], INPUT);
    digitalWrite(ledPins[i],LOW);
    digitalWrite(buttonPins[i],LOW);
  }
  randomSeed(analogRead(0));

}


void loop() {
  Serial.println("Are you ready to play the game?");
  delay(3000);
  if (Serial.available() == 0) {
    playing = true;
  }  

  while (playing) {
    int randNumber;
    randNumber = random(4);
    digitalWrite(ledPins[randNumber], HIGH);
    if (digitalRead(buttonPins[randNumber]) == HIGH) {
      // turn LED off:
      digitalWrite(ledPins[randNumber],LOW);
      score += 1;
      Serial.println("Your score is:");
      Serial.println(score);
    }
    if (score==30) {
      Serial.println("GAME OVER!");
      Serial.println("Your score is:");
      Serial.println(score);
      playing = false;
    }
    delay(1000);
  }
}