#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup(){
  pinMode(3, OUTPUT); pinMode(4, OUTPUT);
  pinMode(5, OUTPUT); pinMode(A0, INPUT);
  lcd.init();
  lcd.setCursor(0, 0);
  lcd.backlight();
  lcd.display();
}

void loop(){
  int val = analogRead(A0); 
  val = map(val, 0, 1023, 0, 255);
  int newVal = val * 100 / 255;
  if (newVal >= 0 && newVal <= 33){
    digitalWrite(3, HIGH);
    digitalWrite(4, LOW);
    digitalWrite(5, LOW);
  } else if (newVal >= 34 && newVal <= 66){
    digitalWrite(3, HIGH);
    digitalWrite(4, HIGH);
    digitalWrite(5, LOW);
  } else if (newVal >= 66 && newVal <= 99){
    digitalWrite(3, HIGH);
    digitalWrite(4, HIGH);
    digitalWrite(5, HIGH);
  } else {
    for (int i = 0; i < 5; i++) { 
      digitalWrite(3, HIGH);
      digitalWrite(4, HIGH);
      digitalWrite(5, HIGH);
      delay(50);
      digitalWrite(3, LOW);
      digitalWrite(4, LOW);
      digitalWrite(5, LOW);
    }
  }
  lcd.setCursor(0, 0);
  lcd.print("Led: ");
  lcd.setCursor(4, 0);
  lcd.print(newVal);
  lcd.print("%");
  delay(500);
  lcd.clear();
}