void setup()
{
  pinMode(3, OUTPUT);
  Serial.begin(9600);
  Serial.println("Please type 'ON' to turn the LED ON");
  Serial.println("Please type 'OFF' to turn the LED OFF");
  Serial.println("Please type 'FLASH' to FLASH the LED");
}

void loop()
{

  if (Serial.available() > 0)
  {
    String input = Serial.readStringUntil('\n');

    if (input == "ON")
    {
      digitalWrite(3, HIGH);
    }
    else if (input == "FLASH")
    {
      for(int x = 0 ;x<5 ;x++)
      {
      
      digitalWrite(3, HIGH);
      delay(500);
      digitalWrite(3, LOW);
      delay(500);
      }
      /*
      digitalWrite(3, HIGH);
      delay(100);
      digitalWrite(3, LOW);
      delay(100);
      digitalWrite(3, HIGH);
      delay(100);
      digitalWrite(3, LOW);
      delay(100);
      digitalWrite(3, HIGH);
      delay(100);
      digitalWrite(3, LOW);
      delay(100);
      digitalWrite(3, HIGH);
      delay(100);
      digitalWrite(3, LOW);*/

    }
    else if(input == "OFF")
    {
      digitalWrite(3, LOW);
    }
    else
    {
      Serial.println("That is not correct,try again");
    }

  }


}