Haunted house project

//<<=== refer to the example of servo > sweep ===>>

#include <Servo.h>

Servo myServo;

int lightReceiver = A0;  //pin: photocell
int led = 6; //pin: LED

int lightDef = 240;  //define the value of brightness
int servoDegr = 40;  //define the original degree of the servo
int rotationSpeed = 25;  //define the speed of servo motion

void setup()
{
  pinMode(lightReceiver, INPUT);
  pinMode(buzzle, OUTPUT);
  pinMode(led, OUTPUT);
  myServo.attach(9);  //pin: servo

  Serial.begin(9600);
}

void loop()
{
  int lightValue = analogRead(lightReceiver); //detect the brightness
  Serial.println(lightValue);
  
  if(lightValue < lightDef)  //activate actuators
  {
    delay(30);
    digitalWrite(led, HIGH); //turn on the LED

    servoDegr -= rotationSpeed;  //spin the servo
    Serial.println(servoDegr);
    if(servoDegr >30 | servoDegr < 20)  //keep servo knock the box
    {
      rotationSpeed *= -1;
    }
    myServo.write(servoDegr);
    delay(550);  //keep the active statement for 550ms
  }

  else
  {
    delay(100);  //
   
    digitalWrite(led, LOW); //turn off the LED
    delay(300); //keep the shaking statement for 300ms

    servoDegr = 40; //recover the original position of servo
    myServo.write(servoDegr);
    delay(15);
  }
}