#define LED 11
#define SWITCH 5

int statoPrecPulsante = LOW;
int statoLED = LOW;

void setup() {
  // put your setup code here, to run once:
  pinMode (LED, OUTPUT);
  pinMode (SWITCH, INPUT);
}

void loop() {
  // put your main code here, to run repeatedl
  int statoPulsante = digitalRead(SWITCH);

  if ((statoPrecPulsante == LOW) && (statoPulsante == HIGH))
  {
    statoLED = !statoLED;
  }

  statoPrecPulsante = statoPulsante;

  if (statoLED == HIGH)
  {
    digitalWrite(LED, HIGH);
  }

  else
  {
    digitalWrite(LED, LOW);
  }

}