int ldrPin = A0;        // LDR connected to analog pin A0
int redLedPin = 12;     // Red LED connected to digital pin 12
int greenLedPin = 13;   // Green LED connected to digital pin 13
int buzzerPin = 11;     // Buzzer connected to digital pin 11 (or any other PWM pin)

void setup() {
  pinMode(redLedPin, OUTPUT);     // Set the red LED pin as output
  pinMode(greenLedPin, OUTPUT);   // Set the green LED pin as output
  pinMode(buzzerPin, OUTPUT);     // Set the buzzer pin as output
  pinMode(ldrPin, INPUT);         // Set the LDR pin as input
  Serial.begin(9600);             // Begin serial communication at 9600 baud
}

void loop() {
  int sensorValue = analogRead(ldrPin);  // Read the value from the LDR
  
  // Print the sensor value for debugging
  Serial.print("LDR Value: ");
  Serial.println(sensorValue);

  if (sensorValue < 500) {              // If the light level is low
    digitalWrite(redLedPin, HIGH);      // Turn on the red LED
    digitalWrite(greenLedPin, LOW);     // Turn off the green LED
    tone(buzzerPin, 1000);              // Play a 1kHz tone on the buzzer
    Serial.println(" Something Detected.");

  } else {                              // If the light level is high
    digitalWrite(redLedPin, LOW);       // Turn off the red LED
    digitalWrite(greenLedPin, HIGH);    // Turn on the green LED
    noTone(buzzerPin);                  // Stop the buzzer sound
    Serial.println(" Nothing detected.");
  }

  delay(1000);  // Wait for 1 second before reading the sensor again
}