---

const int MIC_PIN = A0;
const int LED_GREEN = 9;
const int LED_YELLOW = 10;
const int LED_RED = 11;

const int LOW_THRESHOLD = 150;
const int MID_THRESHOLD = 300;

void setup() {
  pinMode(LED_GREEN, OUTPUT);
  pinMode(LED_YELLOW, OUTPUT);
  pinMode(LED_RED, OUTPUT);

  Serial.begin(9600);
}

void loop() {
  int soundlevel = analogRead(MIC_PIN);
  Serial.println(soundlevel);

  if (soundlevel < LOW_THRESHOLD) {
    digitalWrite(LED_GREEN, HIGH);
    digitalWrite(LED_YELLOW, LOW);
    digitalWrite(LED_RED, LOW);
  }

  else if (soundlevel >= LOW_THRESHOLD && soundlevel < MID_THRESHOLD) {
    digitalWrite(LED_GREEN, HIGH);
    digitalWrite(LED_YELLOW, HIGH);
    digitalWrite(LED_RED, LOW);
  }

  else {
    
      digitalWrite(LED_GREEN, HIGH);
      digitalWrite(LED_YELLOW, HIGH);
      digitalWrite(LED_RED, HIGH);
    }

    delay(50);
  }