const int buttonPin = 2;   // Push button connected to pin 2
const int ledPin = 13;     // LED connected to pin 13

int buttonState = 0;

void setup() {
  // Enable internal pull-up
  pinMode(ledPin, OUTPUT);
   pinMode(buttonPin, INPUT);
}

void loop() {
  buttonState = digitalRead(buttonPin);

  // Button pressed (reads LOW because of pull-up)
  if (buttonState == HIGH) {
    digitalWrite(ledPin, HIGH); // Turn ON light
  } else {
    digitalWrite(ledPin, LOW);  // Turn OFF light
  }
}