#define echoPin 8
#define trigPin 10
const int buzzer = 9;
int led1 = 13;
int led2 = 12;
int led3 = 11;
long duration;
int distance;

void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzer, OUTPUT);
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
  Serial.begin(9600);
  Serial.println("Ultrasonic sensor HC-SRC04 Test");
  Serial.println("With Arduino UNO R3");
}

void loop() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;

  Serial.print("Distance: ");
  Serial.println(distance);
    if (distance < 10) {
    digitalWrite(led2, LOW);
    digitalWrite(led3, HIGH);
    digitalWrite(led1,LOW);
    tone(buzzer, 1000);
    delay(1000);
    noTone(buzzer);
  } else if (distance < 100) {
    digitalWrite(led1, HIGH);
    digitalWrite(led2, LOW);
    digitalWrite(led1, LOW);
    tone(buzzer, 300);
    delay(1000);
    noTone(buzzer);
  } else if(distance >100) {
    digitalWrite(led1, LOW);
    digitalWrite(led3, LOW);
    digitalWrite(led2, HIGH);
    tone(buzzer, 50);
    delay(1000);
    noTone(buzzer);
  }



}