const int LED_PIN_1 = 13;
  const int LED_PIN_2 = 12;
  const int LED_PIN_3 = 11;
  const int button_1 = 7;
  const int button_2 = 6;
  const int button_3 = 5;
  const int button_4 = 4;
  const int Buzzer_Pin = 10;

  
  int ButtonState1 = 0;
  int ButtonState2 = 0;
  int ButtonState3 = 0;
  int ButtonState4 = 0;
  int LED_PIN_2BlinkDelay = LOW;
  int LED_PIN_3_Brightness = 0;

void setup() {
  pinMode(LED_PIN_1, OUTPUT);
  pinMode(LED_PIN_2, OUTPUT);
  pinMode(LED_PIN_3, OUTPUT);
  pinMode(button_1, INPUT_PULLUP);
  pinMode(button_2, INPUT_PULLUP);
  pinMode(button_3, INPUT_PULLUP);
  pinMode(button_4, INPUT_PULLUP);
  pinMode(Buzzer_Pin, OUTPUT);

}

void loop() {

  ButtonState1 = digitalRead(button_1);
  if (digitalRead(ButtonState1) == HIGH)
  { digitalWrite(LED_PIN_1, HIGH);
    tone(Buzzer_Pin, 350);
  }
  else {
    digitalWrite(LED_PIN_1, LOW);
    noTone(Buzzer_Pin);
  }
  ButtonState2 = digitalRead(button_2);
  if (digitalRead(ButtonState2) == HIGH)
  {
    LED_PIN_2BlinkDelay = 100;
  }
  
  ButtonState3 = digitalRead(button_3);
  if (digitalRead(ButtonState3) == HIGH)
  {
    LED_PIN_2BlinkDelay = 1500;
  }
  digitalWrite(LED_PIN_2, HIGH);
  delay(LED_PIN_2BlinkDelay);
  digitalWrite(LED_PIN_2, LOW);
  delay(LED_PIN_2BlinkDelay);

  ButtonState4 = digitalRead(button_4);
  if (digitalRead(ButtonState4) == HIGH)
  {
    LED_PIN_3_Brightness = 255;
  }
  else (digitalRead(ButtonState4) == LOW);
  {
    LED_PIN_3_Brightness = 0;
  } 
 
  
  
}