// Declarar variables y botones
int led = 12;
int botonOn = 15;
int botonOff = 4;
int botonOnOff = 16;

// Declaro el estado del led
bool state = false;

void setup() {
  // Iniciamos los pines para botones y leds
  pinMode(led, OUTPUT);
  pinMode(botonOn, INPUT_PULLUP);
  pinMode(botonOff, INPUT_PULLUP);
  pinMode(botonOnOff, INPUT_PULLUP);
}

void loop() {
  // Lecturas digitales para
  if(digitalRead(botonOn)==LOW){
    if(!state){
      digitalWrite(led, HIGH);
      state = true;
    }
    while(digitalRead(botonOff)==LOW){}
  }

  if(digitalRead(botonOff)==LOW){
    if(!state){
      digitalWrite(led, HIGH);
      state = false;
    }
    while(digitalRead(botonOff)==LOW){}
  }
  
  if(digitalRead(botonOnOff)==LOW){
    if(state){
      digitalWrite(led, LOW);
      state = false;
    } else {
      digitalWrite(led, HIGH);
      state = true;
    }
    while(digitalRead(botonOnOff)==LOW){}
  }
}