---

#define PHOTO_PIN A0

#define RED_LED 3
#define GREEN_LED 5
#define YELLOW_LED 6

void setup() {
  pinMode(RED_LED, OUTPUT);
  pinMode(GREEN_LED, OUTPUT);
  pinMode(YELLOW_LED, OUTPUT);

  Serial.begin(9600);
}

void loop() {
  int light = analogRead(PHOTO_PIN);

  Serial.println(light);

  if (light > 960) {
    digitalWrite(RED_LED, HIGH);
    digitalWrite(GREEN_LED, LOW);
    digitalWrite(YELLOW_LED, LOW);
  }
  else if (light > 900) {
    digitalWrite(RED_LED, LOW);
    digitalWrite(GREEN_LED, HIGH);
    digitalWrite(YELLOW_LED, LOW);
  }
  else {
    digitalWrite(RED_LED, LOW);
    digitalWrite(GREEN_LED, LOW);
    digitalWrite(YELLOW_LED, HIGH);
  }

  delay(200);
}