int pin2 = 2;
//int Brightness = 255;
int pin3 = 3;
int pin4 = 4;
int pin5 = 5;

String myNum;
String msg = "Enter a number from 0 to 15: ";


void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(pin2, OUTPUT);
  pinMode(pin3, OUTPUT);
  pinMode(pin4, OUTPUT);
  pinMode(pin5, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.println(msg);

  while (Serial.available() == 0 )
  {

  }

  myNum = Serial.readString();  
  myNum.trim();

  if(myNum == "0"){
    digitalWrite(pin2, LOW);
    digitalWrite(pin3, LOW);
    digitalWrite(pin4, LOW);
    digitalWrite(pin5, LOW);
    delay(250);
  }

  if(myNum =="1"){
    digitalWrite(pin2, LOW);
    digitalWrite(pin3, LOW);
    digitalWrite(pin4, LOW);
    digitalWrite(pin5, HIGH);
    delay(250);
  }

  if(myNum.equals("2")){
    digitalWrite(pin2, LOW);
    digitalWrite(pin3, LOW);
    digitalWrite(pin4, HIGH);
    digitalWrite(pin5, LOW);
    delay(250);
  }
  if(myNum.equals("3")){
    digitalWrite(pin2, LOW);
    digitalWrite(pin3, LOW);
    digitalWrite(pin4, HIGH);
    digitalWrite(pin5, HIGH);
    delay(250);
  }
  if(myNum.equals("4")){
    digitalWrite(pin2, LOW);
    digitalWrite(pin3, HIGH);
    digitalWrite(pin4, LOW);
    digitalWrite(pin5, LOW);
    delay(250);
  }
  if(myNum.equals("5")){
    digitalWrite(pin2, LOW);
    digitalWrite(pin3, HIGH);
    digitalWrite(pin4, LOW);
    digitalWrite(pin5, HIGH);
    delay(250);
  }
  if(myNum.equals("6")){
    digitalWrite(pin2, LOW);
    digitalWrite(pin3, HIGH);
    digitalWrite(pin4, HIGH);
    digitalWrite(pin5, LOW);
    delay(250);
  }
  if(myNum.equals("7")){
    digitalWrite(pin2, LOW);
    digitalWrite(pin3, HIGH);
    digitalWrite(pin4, HIGH);
    digitalWrite(pin5, HIGH);
    delay(250);
  }
  if(myNum.equals("8")){
    digitalWrite(pin2, HIGH);
    digitalWrite(pin3, LOW);
    digitalWrite(pin4, LOW);
    digitalWrite(pin5, LOW);
    delay(250);
  }
  if(myNum.equals("9")){
    digitalWrite(pin2, HIGH);
    digitalWrite(pin3, LOW);
    digitalWrite(pin4, LOW);
    digitalWrite(pin5, HIGH);
    delay(250);
  }
  if(myNum.equals("10")){
    digitalWrite(pin2, HIGH);
    digitalWrite(pin3, LOW);
    digitalWrite(pin4, HIGH);
    digitalWrite(pin5, LOW);
    delay(250);
  }
  if(myNum.equals("11")){
    digitalWrite(pin2, HIGH);
    digitalWrite(pin3, LOW);
    digitalWrite(pin4, HIGH);
    digitalWrite(pin5, HIGH);
    delay(250);
  }
  if(myNum.equals("12")){
    digitalWrite(pin2, HIGH);
    digitalWrite(pin3, HIGH);
    digitalWrite(pin4, LOW);
    digitalWrite(pin5, LOW);
    delay(250);
  }
  if(myNum.equals("13")){
    digitalWrite(pin2, HIGH);
    digitalWrite(pin3, HIGH);
    digitalWrite(pin4, LOW);
    digitalWrite(pin5, HIGH);
    delay(250);
  }
  if(myNum.equals("14")){
    digitalWrite(pin2, HIGH);
    digitalWrite(pin3, HIGH);
    digitalWrite(pin4, HIGH);
    digitalWrite(pin5, LOW);
    delay(250);
  }
  if(myNum.equals("15")){
    digitalWrite(pin2, HIGH);
    digitalWrite(pin3, HIGH);
    digitalWrite(pin4, HIGH);
    digitalWrite(pin5, HIGH);
    delay(250);
  }
  else{
    Serial.println("invalid input");
  }
}