const int trigPin = 4;
const int echoPin = 18;
const int buzzer = 2;

long duration;
int distance;

void setup() {
  // put your setup code here, to run once:
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, OUTPUT);
  pinMode(buzzer,OUTPUT);
   pinMode(5, OUTPUT);
  Serial.begin(9600);
  // Serial.println("Hello, ESP32!");
}

void loop() 
{
  // put your main code here, to run repeatedly:

  // Clears the trigPin

digitalWrite(trigPin, LOW);
delayMicroseconds(2);
	// Sets the trigPin on HIGH state for 10 micro seconds
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);

	// Reads the echoPin, returns the sound wave travel time in microsec.
duration = pulseIn(echoPin, HIGH);
	// Calculating the distance
distance= (duration*0.034)/2;
	// Prints the distance on the Serial Monitor
Serial.print("Distance: ");
Serial.print(distance);
Serial.println("cm");
delay(500);  //500 m.sec = 0.5 sec

tone(buzzer, 1000); 
  delay(1000); 
 noTone(buzzer);     
  delay(1000);  
  digitalWrite(5, HIGH);
  delay(1000);

}