int led = 13;                
int sensor = 2;
int buzzer=12;              
int state = LOW;             
int val = 0;
int count = 1;             

void setup() {
  pinMode(led, OUTPUT); 
      
  pinMode(sensor, INPUT);    
  Serial.begin(9600);        
}

void loop(){
  val = digitalRead(sensor);   
  if (val == HIGH) {          
    digitalWrite(led, HIGH);  
    
    digitalWrite(buzzer, HIGH);
    tone(buzzer,500,500);
    delay(100);                
    
    if (state == LOW) {
      Serial.println("Motion detected!"); 
      Serial.println(count);
      count++;
      state = HIGH;      
    }
  } 
  else {
      digitalWrite(led, LOW);
      delay(2000);
      digitalWrite(buzzer, LOW);
      delay(200);             
      
      if (state == HIGH){
        Serial.println("Motion stopped!");
        state = LOW;       
    }
  }
}