// Define pin numbers
static const uint8_t LED_PIN = 2U;
static const uint8_t BUTTON_PIN = 4U;

void setup(void) {
    pinMode(LED_PIN, OUTPUT);
    pinMode(BUTTON_PIN, INPUT_PULLUP);  // Internal pull-up resistor

    digitalWrite(LED_PIN, LOW);  // Ensure LED starts OFF
}

void loop(void) {
    uint8_t buttonState = digitalRead(BUTTON_PIN);

    if (buttonState == LOW) {  
        digitalWrite(LED_PIN, HIGH);  // Turn LED ON when button is pressed
    } else {
        digitalWrite(LED_PIN, LOW);   // Turn LED OFF when button is released
    }
}