int LDRSensor = 36;
 int led=32;
 int PIRSensor=2;
 int buzzer=4;
 int state = LOW;             
 int val = 0;

void setup()
 {

  pinMode (LDRSensor, INPUT);
  pinMode(led, OUTPUT);
  pinMode(buzzer, OUTPUT);      
  pinMode(PIRSensor, INPUT);
  Serial.begin (9600);
 }
 
void loop()
{
  LDR();
  PIR();

}

//Automatic light on and off
void LDR()
 {
  int Sensordata = analogRead (LDRSensor);
  Serial.print("Sensor value:");
  Serial.println(Sensordata);
  delay(100);
  if (Sensordata > 600)
    digitalWrite(led, HIGH); 
  else
    digitalWrite(led, LOW); 

 }
//security system
 void PIR(){
  val = digitalRead(PIRSensor);   
  if (val == HIGH) {           
    digitalWrite(buzzer, HIGH);   
    delay(500);                 
    if (state == LOW) {
      Serial.println("Motion detected!"); 
      state = HIGH;       
    }
  } 
  else {
      digitalWrite(buzzer, LOW); 
      delay(500);  
      if (state == HIGH){
        Serial.println("Motion stopped!");
        state = LOW;       
    }
  }
}