int vr_pin = A0;
int led_pin = 11;
void setup() {
  pinMode(vr_pin, INPUT);
  pinMode(led_pin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int vr = analogRead(vr_pin);
  int vrl = map(vr,0,1023,0,255);
  analogWrite(led_pin,vrl);
  Serial.println(vrl);
  delay(500);
}