#define triggerPin 2 // Pin connected to the TRIGGER pin of the ultrasonic sensor
#define echoPin 4    // Pin connected to the ECHO pin of the ultrasonic sensor
#define buzzerPin 5  // Pin connected to the buzzer
int beepcount = 0 ; // variable to trak the number of beeps 
void setup() {
  pinMode(triggerPin, OUTPUT);// Initialize the TRIGGER pin as an output
  pinMode(echoPin, INPUT);   // Initialize the ECHO pin as an input
  pinMode(buzzerPin, OUTPUT);// Initialize the buzzer pin as an output
}

void loop() {
  // Generate trigger pulse
  digitalWrite(triggerPin, LOW);
  delayMicroseconds(2);
  digitalWrite(triggerPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(triggerPin, LOW);

  // Measure the pulse from the echo pin
  long duration = pulseIn(echoPin, HIGH);

  // Convert the pulse duration to distance
  int distance = duration * 0.0343 / 2; //  we devide the speed by 2 because the sound has to travel forward and back

  // If an object is detected within 100cm, activate the buzzer
  if (distance < 100 && beepcount <2 ) {
    tone(buzzerPin, 100, 100); // Generate a 100ms beep
    delay(100);                 // Wait for 100ms
    noTone(buzzerPin);          // Turn off the buzzer
    delay(100);                 // Wait for 100ms
    beepcount++;                //increment the beepcount
  }
  delay(1000); // Wait for 1000ms before the next reading 
  if (distance >=100){
    beepcount=0;
    //reset beepcount if no object is detected
  }
}