#define BUZZER_PIN 12
#define PLAYER_COUNT 2
int buttonPins[PLAYER_COUNT] = {3, 13};
int ledPins[PLAYER_COUNT] = {9, 11};
int startTime;
int deltaTime;

void setup(){
  pinMode(BUZZER_PIN, OUTPUT);
  for(int player = 0; player < PLAYER_COUNT; ++player){
    pinMode(ledPins[player], OUTPUT);
    pinMode(buttonPins[player], INPUT_PULLUP);
  }
}
void loop(){
  startTime = millis();
  deltaTime = random(2000, 7000);
  tone(BUZZER_PIN, 3000, 250);
  for(int player = 0; ; player = (player + 1) % PLAYER_COUNT) {
    if (millis() < startTime + deltaTime) {
      if (!digitalRead(buttonPins[player])) {
        tone(BUZZER_PIN, 4000, 1000);
        digitalWrite(ledPins[(player + 1) % PLAYER_COUNT], HIGH);
        delay(1000);
        digitalWrite(ledPins[(player + 1) % PLAYER_COUNT], LOW);
        break;
      }
    } else {
      tone(BUZZER_PIN, 3000, 250);
      for(int player = 0; ; player = (player + 1) % PLAYER_COUNT) {
        if (!digitalRead(buttonPins[player])) {
          tone(BUZZER_PIN, 4000, 1000);
          digitalWrite(ledPins[player], HIGH);
          delay(1000);
          digitalWrite(ledPins[player], LOW);
          break;
        }
      }
      break;
    }
  }
}