int v=0; 
int nodeid=1;

void setup() {
  Serial.begin(9600); 
  pinMode(LED_BUILTIN, OUTPUT); // white led
}

void loop() {
  while (Serial.available () == 0 ) {}
  v = Serial.parseInt();
  Serial.println(v);
  if(v == nodeid)
{
  digitalWrite(LED_BUILTIN,HIGH);
  delay(500);
  digitalWrite(LED_BUILTIN,LOW);
  delay(500);
  digitalWrite(LED_BUILTIN,HIGH);
  delay(500);
  digitalWrite(LED_BUILTIN,LOW);
}
else
{
  digitalWrite(LED_BUILTIN,LOW);
 }
}