const int button_pin = 8;
int button_value;
void setup() {
  pinMode(button_pin,INPUT_PULLUP);
  pinMode(LED_BUILTIN, OUTPUT);

  Serial.begin(9600);

  // put your setup code here, to run once:

}

void loop() {
  button_value = !digitalRead(button_pin);
  Serial.println(button_value);

  digitalWrite(LED_BUILTIN,button_value);
  // put your main code here, to run repeatedly:

}