// Define the pins for the ultrasonic sensor, buzzer, and LED
const int trigPin = 18;
const int echoPin = 5;
const int buzzerPin = 4;
const int ledPin = 2;

// Variables to store the duration and distance
long duration;
int distance;

void setup() {
  // Initialize the serial communication
  Serial.begin(9600);

  // Define pins as OUTPUT or INPUT
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
}

void loop() {
  // Generate a 10us pulse to trigger the ultrasonic sensor
  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.print(distance);
  Serial.println(" cm");

  if (distance < 50) {
    playTone(buzzerPin, 1000, 200);
  } else {
    digitalWrite(buzzerPin, LOW);
  }

  delay(1000);
}

void playTone(int pin, int frequency, int duration) {
  tone(pin, frequency);
  digitalWrite(ledPin, HIGH); // Turn on the LED
  delay(duration);
  noTone(pin);
  digitalWrite(ledPin, LOW); // Turn off the LED
}








// // Define the pins for the ultrasonic sensor, buzzer, and LED
// const int trigPin = 18;
// const int echoPin = 5;
// const int buzzerPin = 4;
// const int ledPin = 2;

// // Variables to store the duration and distance
// long duration;
// int distance;

// void setup() {
//   // Initialize the serial communication
//   Serial.begin(9600);

//   // Define pins as OUTPUT or INPUT
//   pinMode(trigPin, OUTPUT);
//   pinMode(echoPin, INPUT);
//   pinMode(buzzerPin, OUTPUT);
//   pinMode(ledPin, OUTPUT);
// }

// void loop() {
//   // Generate a 10us pulse to trigger the ultrasonic sensor
//   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.print(distance);
//   Serial.println(" cm");

//   if (distance < 50) {
//     playSiren(buzzerPin, 2000, 3000, 200);
//   } else {
//     digitalWrite(buzzerPin, LOW);
//   }

//   delay(1000);
// }

// void playSiren(int pin, int frequency1, int frequency2, int duration) {
//   for (int i = 0; i < duration; i++) {
//     tone(pin, frequency1);
//     digitalWrite(ledPin, HIGH); // Turn on the LED
//     delay(100);
//     noTone(pin);
//     digitalWrite(ledPin, LOW); // Turn off the LED
//     delay(100);
//     tone(pin, frequency2);
//     digitalWrite(ledPin, HIGH); // Turn on the LED
//     delay(100);
//     noTone(pin);
//     digitalWrite(ledPin, LOW); // Turn off the LED
//     delay(100);
//   }
// }








// // Define the pins for the ultrasonic sensor, buzzer, and LED
// const int trigPin = 18;
// const int echoPin = 5;
// const int buzzerPin = 4;
// const int ledPin = 2;

// // Variables to store the duration and distance
// long duration;
// int distance;

// void setup() {
//   // Initialize the serial communication
//   Serial.begin(9600);

//   // Define pins as OUTPUT or INPUT
//   pinMode(trigPin, OUTPUT);
//   pinMode(echoPin, INPUT);
//   pinMode(buzzerPin, OUTPUT);
//   pinMode(ledPin, OUTPUT);
// }

// void loop() {
//   // Generate a 10us pulse to trigger the ultrasonic sensor
//   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.print(distance);
//   Serial.println(" cm");

//   if (distance < 50) {
//     playMarioTone();
//   } else {
//     digitalWrite(buzzerPin, LOW);
//   }

//   delay(1000);
// }

// void playMarioTone() {
//   int melody[] = {659, 659, 0, 659, 0, 523, 659, 0, 784, 0, 392, 0, 523, 0, 392, 0};
//   int noteDuration[] = {125, 125, 125, 125, 125, 125, 125, 125, 125, 125, 125, 125, 125, 125, 125, 125};
  
//   for (int i = 0; i < sizeof(melody) / sizeof(melody[0]); i++) {
//     if (melody[i] == 0) {
//       noTone(buzzerPin);
//     } else {
//       tone(buzzerPin, melody[i]);
//     }
//     delay(noteDuration[i]);
//     noTone(buzzerPin);
//     delay(50); // Add a small pause between notes
//   }
// }