#include <Adafruit_NeoPixel.h>

#define PIN 6
#define NUMPIXELS 16 

Adafruit_NeoPixel pixels(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

const int potPin = A0;

void setup() {
  pixels.begin();
  pixels.show();
}

void loop() {
  int potValue = analogRead(potPin);
  int numLEDs = map(potValue, 0, 1023, 0, NUMPIXELS);
  pixels.clear();
  
  for (int i = 0; i < numLEDs; i++) {
    if (numLEDs<5){
    pixels.setPixelColor(i, pixels.Color(0, 255, 0)); // amarelo RGB
    } 
    if (numLEDs>=5 && numLEDs<9){
    pixels.setPixelColor(i, pixels.Color(255, 255, 0)); // laranja
    } 
    if (numLEDs>=9 && numLEDs<=13){
    pixels.setPixelColor(i, pixels.Color(255, 128, 0)); // vermelho
    } 
    if (numLEDs>13){
    pixels.setPixelColor(i, pixels.Color(255, 0, 0)); // amarelo RGB
    } 
  }
  pixels.show(); 
  delay(50);
}