int NUM_CANDLES = 9;
int candles[] = [0, 1, 2, 3, 4, 5, 6, 7, 8]; // Define the pins for each candle. First is shamash
int btn = 10; // Define the pin for the button

int ner = 0;

// the setup routine runs once when you press reset:
void setup() {
  // initialize each candle pin to OUTPUT
  for (int i = 0; i < NUM_CANDLES; i++) {
    pinMode(candles[i], OUTPUT);
  }

  // initialize the button pin to INPUT with the built in pullup resistor
  pinMode(btn, INPUT_PULLUP);
}

// the loop routine runs over and over again forever:
void loop() {

  if (digitalRead(btn) == HIGH) {
    // Button is not pressed
  } else {
    // Button was pressed!
    ner++;
    ner %= 8;
  }

  for (int i = 0; i < NUM_CANDLES; i++) {
    if (i >= ner) {
      digitalWrite(candles[i], HIGH); // Turn the candle on
    } else {
      digitalWrite(candles[i], LOW); // Turn the candle off
    }
  }
}