#include <Keypad.h>
#include <LiquidCrystal_I2C.h>
#include <Wire.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);
const uint8_t ROWS = 4;
const uint8_t COLS = 4;
char keys[ROWS][COLS] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};

uint8_t colPins[COLS] = { 5, 4, 3, 2 }; // Pins connected to C1, C2, C3, C4
uint8_t rowPins[ROWS] = { 9, 8, 7, 6 }; // Pins connected to R1, R2, R3, R4

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);
String code = "1234";
String pass = "";
bool start;
void setup() {
  lcd.init();
  lcd.backlight();
  Serial.begin(9600);
    for(int i = 0; i <= 2; i++){
    lcd.setCursor(5, 0);
    lcd.print("Loading");
    delay(300);
    lcd.setCursor(5, 0);
    lcd.print("Loading.");
    delay(300);
    lcd.setCursor(5, 0);
    lcd.print("Loading..");
    delay(300);
    lcd.setCursor(5, 0);
    lcd.print("Loading...");
    delay(300);
    lcd.setCursor(12, 0);
    lcd.print("   ");
  }
  start = true;
  lcd.clear();
}

void loop() {
  char key = keypad.getKey();
  if(start){
    lcd.print("Enter Code");

    if (key != NO_KEY) {
      pass += key;
    }

    if(pass.length() == 4){
      if(pass == code){
        lcd.setCursor(5, 0);
        lcd.print("Correct");
      }
      else{
        lcd.setCursor(5, 0);
        lcd.print("Incorrect");
        delay(2000);
        lcd.clear();
        pass = "";
      }
    }
    else{
      lcd.setCursor(5, 0);
      lcd.print(pass);
    }
  }

}