int LED_VERMELHO = 4;
int LED_AMARELO = 3;
int LED_VERDE = 2;

bool ledState[] = {LOW,LOW,LOW};
unsigned long currentTime = 0;
unsigned long previousTime[] = {0,0,0};

int leds[] ={2, 3, 4};

void setup(){
  Serial.begin(9600);
  for(int i = 0; i < 3; i++){
  	pinMode(leds[i], OUTPUT);
  }
}


void tarefa(int pin, int interval){
  //Serial.println(pin);
  currentTime = millis();
  interval /= 2;
  if((currentTime - previousTime[pin-2]) >= interval) {
  	previousTime[pin-2] = currentTime;
    bool state = !ledState[pin-2];
    ledState[pin-2] = state;
    digitalWrite(pin, state);
  }
  
}


void loop()
{	
  
  tarefa(LED_VERMELHO, 2000);
  tarefa(LED_AMARELO, 1000);
  tarefa(LED_VERDE, 500);
  
  	
}