// Define the number of LEDs
const int numLEDs = 10;

// Define the pins for the LEDs
int ledPins[] = {2, 3, 4, 5, 6, 7, 8, 9, 10, 11};

void setup() {
  // Initialize the LED pins as outputs
  for (int i = 0; i < numLEDs; i++) {
    pinMode(ledPins[i], OUTPUT);
  }
}

void loop() {
  // Turn on each LED in sequence
  for (int i = 0; i < numLEDs; i++) {
    digitalWrite(ledPins[i], HIGH);
    delay(100);  // Adjust the delay as needed
    digitalWrite(ledPins[i], LOW);
  }

  // Turn off each LED in reverse sequence
  for (int i = numLEDs - 1; i >= 0; i--) {
    digitalWrite(ledPins[i], HIGH);
    delay(100);  // Adjust the delay as needed
    digitalWrite(ledPins[i], LOW);
  }
}