#define TRIG_PIN 14
#define ECHO_PIN 12
#define LED_PIN 27
long duration;
int distance;


void setup() {
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(LED_PIN, OUTPUT);
  Serial.begin(115200);
}


void loop() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = duration * 0.034 / 2;
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");
 
  int blinkCount = 0;
  if (distance <= 200 && distance > 150) {
    blinkCount = 5;
  } else if (distance <= 150 && distance > 100) {
    blinkCount = 4;
  } else if (distance <= 100 && distance > 50) {
    blinkCount = 3;
  }
 
  if (blinkCount > 0) {
    for (int i = 0; i < blinkCount; i++) {
      digitalWrite(LED_PIN, HIGH);
      delay(200);
      digitalWrite(LED_PIN, LOW);
      delay(200);
    }
  } else {
    digitalWrite(LED_PIN, LOW);
  }
  delay(500);
}