#include <Adafruit_NeoPixel.h>;
int Pin = 12;
int N_led = 16;


Adafruit_NeoPixel ring = Adafruit_NeoPixel(N_led,Pin);

void setup() {
  // put your setup code here, to run once:
  ring.begin();
}

void loop() {
  // put your main code here, to run repeatedly:
  for(int i=0; i<N_led; i++ ){
    ring.setPixelColor(i,ring.Color(0,0,255));
    ring.show();
    delay(500);
     if (i < 8){
      ring.setPixelColor(i,ring.Color(255,0,0));
      ring.show();
      delay(500);
     }
     else{
      ring.setPixelColor(i,ring.Color(0,255,0));
      ring.show();
      delay(500);
     }
  }
}