uint16_t count = 0;

void setup() {
  Serial.begin(115200);
  // put your setup code here, to run once:
  pinMode(9, INPUT);

}

void loop() {
  // put your main code here, to run repeatedly:
  if (digitalRead(9)) {
    while (digitalRead(9)) {}
    count ++;
    Serial.println(count);
  }
}