#define sw 2
#define led 13
int i=0;
void setup() {
  Serial.begin(9600);
  pinMode(sw,INPUT_PULLUP);
  pinMode(led,OUTPUT);

}

void loop() {
  while(digitalRead(sw)==LOW)
  {
    digitalWrite(led, HIGH);
  }
  digitalWrite(led,LOW);
  Serial.println(i);
  i++;

}