const int rojo = 7;
const int verde = 8;
const int azul = 9;

void setup(){
  pinMode(rojo, OUTPUT);
  pinMode(verde, OUTPUT);
  pinMode(azul, OUTPUT);
  pinMode(A0, INPUT);
  Serial.begin(9600);
}

void loop(){
  if (analogRead(A0)<=300){
    digitalWrite(rojo, HIGH);
    digitalWrite(verde, LOW);
    digitalWrite(azul, LOW);
  }
  if (analogRead(A0)>300 && analogRead(A0)<=900){
    digitalWrite(rojo, LOW);
    digitalWrite(verde, HIGH);
    digitalWrite(azul, LOW);
  }
  if (analogRead(A0)>=900) {
    digitalWrite(rojo, LOW);
    digitalWrite(verde, LOW);
    digitalWrite(azul, HIGH);
  }
  Serial.println(analogRead(A0));
  delay(500);
}