#include <Wire.h> 
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);

void setup() {
  Serial.begin(9600);
  pinMode(A0, INPUT);
  pinMode(2, INPUT);
  pinMode(3, OUTPUT);
  lcd.init();
  lcd.backlight();
}

void loop() {
  lcd.clear();
  lcd.print(analogRead(A0));
  digitalWrite(3, digitalRead(2));
  delay(500); 
}