#define BUTTON_PIN 4
void setup() 
 {
  Serial.begin(115200);
  pinMode(BUTTON_PIN, INPUT_PULLUP);
}
int counter = 0;
int lastState = HIGH;
void loop()
 {
  int value = digitalRead((BUTTON_PIN));
  if (lastState != value)
   {
    counter++;
    lastState = value;
    Serial.println(counter);
  }
}