#include <Ultrasonic.h>

const int LDRPin = A0;        // LDR sensor connected to analog pin A0
const int trigPin = 7;        // Ultrasonic sensor trig pin connected to digital pin 7
const int echoPin = 6;        // Ultrasonic sensor echo pin connected to digital pin 6
const int buzzerPin = 9;      // Buzzer connected to digital pin 9
const int ledPin = 11;        // LED connected to digital pin 11
int ldrThreshold = 500;       // Threshold value for LDR sensor
int distanceThreshold = 50;   // Threshold distance for Ultrasonic sensor
int buzzerDuration = 500;     // Duration for buzzer activation (in milliseconds)
int ledDuration = 500;        // Duration for LED activation (in milliseconds)
int ldrValue = 0;             // variable to store LDR sensor value
int distance = 0;             // variable to store ultrasonic sensor distance value

Ultrasonic ultrasonic(trigPin, echoPin);  // create ultrasonic sensor object

void setup() {
  pinMode(LDRPin, INPUT);              // set LDR pin as input
  pinMode(trigPin, OUTPUT);            // set ultrasonic sensor trig pin as output
  pinMode(echoPin, INPUT);             // set ultrasonic sensor echo pin as input
  pinMode(buzzerPin, OUTPUT);          // set buzzer pin as output
  pinMode(ledPin, OUTPUT);             // set LED pin as output
  Serial.begin(9600);                  // start serial communication
}

void loop() {
  ldrValue = analogRead(LDRPin);        // read LDR sensor value
  distance = ultrasonic.read();        // read ultrasonic sensor value

  if (ldrValue < ldrThreshold && distance < distanceThreshold) {   // if both sensors detect an object
    Serial.println("Object detected!");                            // print message to serial monitor
    digitalWrite(buzzerPin, HIGH);     // turn on the buzzer
    digitalWrite(ledPin, HIGH);        // turn on the LED
    delay(buzzerDuration);             // wait for the specified duration
    digitalWrite(buzzerPin, LOW);      // turn off the buzzer
    digitalWrite(ledPin, LOW);         // turn off the LED
    delay(ledDuration);                // wait for the specified duration
  }
}

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

}