int valor;
void setup() {
  // put your setup code here, to run once:
  pinMode (5, OUTPUT);
  pinMode (A3, INPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  valor = analogRead(A3);
  Serialt.println(valor);
  valor = map (valor, 0, 1023, 0, 255);
  Serial.println(valor);
  analogWrite (5,valor);
}