//Define LED pin
int ledPin = 16; 
// setup() function is for initialization
// it only runs once
void setup() {
  pinMode(ledPin, OUTPUT);
}

// loop() function, like its name, keep running over and over (looping)
void loop() {
  
  digitalWrite(ledPin, HIGH); 
  
  delay(1000); 

  digitalWrite(ledPin, LOW); 
  delay(1000);
}