const int ledPins[5] = {2, 3, 4, 5, 6};  // LED pins
int count = 0;   // Start at 0
bool up = true;  // Counting direction (true = up, false = down)

void setup() {
  for (int i = 0; i < 5; i++) {
    pinMode(ledPins[i], OUTPUT);
  }
}

void loop() {
  // Display the binary number using LEDs
  for (int i = 0; i < 5; i++) {
    digitalWrite(ledPins[i], bitRead(count, i));
  }

  // Change count direction when reaching 0 or 31
  if (count == 31) {
    up = false;  // Start counting down
  } else if (count == 0) {
    up = true;   // Start counting up
  }

  // Increment or decrement count
  count += up ? 1 : -1;

  delay(500);  // Wait 500ms
}