int LDR_PIN = A0; 
int LAMP_PIN = 3; 
int BELL_PIN = 4; 
int MOTION_PIN = 2; 

void setup() {
  pinMode(LDR_PIN, INPUT);
  pinMode(MOTION_PIN, INPUT);
  pinMode(LAMP_PIN, OUTPUT);
  pinMode(BELL_PIN, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int lightLevel = analogRead(LDR_PIN); 
  // Read the light level
  int motionDetected = digitalRead(MOTION_PIN); 
  // Check for motion
  if (lightLevel < 512 && motionDetected == HIGH) { 
    digitalWrite(LAMP_PIN, HIGH); 
    digitalWrite(BELL_PIN, HIGH); 
    tone(4,262,250);
  } else if (lightLevel >= 512 && motionDetected == HIGH) {
    digitalWrite(LAMP_PIN, LOW); 
    digitalWrite(BELL_PIN, HIGH); 
    tone(4,262,250);
  } else {
    digitalWrite(LAMP_PIN, LOW); 
    digitalWrite(BELL_PIN, LOW); 
  }
  
  delay(100); 
}