int leds[5] = {13, 12, 11, 10, 9};   // pin numbers for the LEDs
int buttons[5] = {2, 3, 4, 5, 6};    // pin numbers for the buttons
int order[5];                        // array to hold the order of the buttons
int current_button = 0;              // current button to light up
int num_buttons = 5;                 // number of buttons in the game
int player1_score = 0;               // player 1's score
int player2_score = 0;               // player 2's score

void setup() {
  randomSeed(analogRead(0));         // seed the random number generator
  Serial.begin(9600);                // initialize serial communication
  pinMode(LED_BUILTIN, OUTPUT);      // initialize built-in LED as output
  for (int i = 0; i < num_buttons; i++) {
    pinMode(leds[i], OUTPUT);        // initialize LEDs as output
    pinMode(buttons[i], INPUT_PULLUP); // initialize buttons as input
    order[i] = i;                    // initialize order array
  }
  shuffleButtons();                  // shuffle the order of the buttons
}

void loop() {
  digitalWrite(LED_BUILTIN, HIGH);   // turn on built-in LED
  for (int i = 0; i < num_buttons; i++) {
    digitalWrite(leds[order[i]], HIGH); // light up the next button
    delay(500);                      // wait for half a second
    digitalWrite(leds[order[i]], LOW);  // turn off the LED
    delay(500);                      // wait for half a second
  }
  current_button = 0;                // start with the first button
  while (current_button < num_buttons) {
    int player = current_button % 2 + 1;  // determine which player is playing
    int button = waitForButton(player);  // wait for the player to press the button
    if (button == buttons[order[current_button]]) { // if it's the right button
      if (player == 1) {
        player1_score++;             // increment player 1's score
      } else {
        player2_score++;             // increment player 2's score
      }
      current_button++;              // move on to the next button
    }
  }
  Serial.print("Player 1 score: ");
  Serial.println(player1_score);     // print player 1's score
  Serial.print("Player 2 score: ");
  Serial.println(player2_score);     // print player 2's score
  delay(1000);                       // wait for a second before starting again
  shuffleButtons();                  // shuffle the order of the buttons
}

int waitForButton(int player) {
  while (1) {
    for (int i = 0; i < num_buttons; i++) {
      if (digitalRead(buttons[i]) == LOW) {
        return buttons[i];           // return the button that was pressed
      }
    }
  }
}

void shuffleButtons() {
  for (int i = 0; i < num_buttons; i++) {
    int j = random(i, num_buttons); // choose a random index from i to the end
      if (i != j) {  // swap the values at index i and j in the order array
        int temp = order[i];
          order[i] = order[j];
          order[j] = temp;
      }
    }
}