#include <Keypad.h>
#include <LiquidCrystal_I2C.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 klava = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);
byte x = 0;

int rele = 10;
int kod = 4273;
int vvod = 0;
bool flag = 0;
void setup() {
  Serial.begin(9600);
  lcd.init();
  lcd.backlight();
  lcd.setCursor(1, 0);
  lcd.print("Enter Password");
  pinMode(rele, OUTPUT);
}

void loop() {
  char key = klava.getKey();
  if (key != NO_KEY) {
    //Serial.println(key);
    lcd.setCursor(x, 1);
    lcd.print(key);
    //Serial.println(int(key) - 48);
    int k = int(key)-48;
    if (4 == 4) {
      EEPROM.write(x, k);
    }
    vvod = vvod + k*pow(10, 3-x);
    x++;
  }
  if (x == 4) {
    if (flag == 0);{
     flag = 1;
     Serial.println(EEPROM.read(0));
     Serial.println(EEPROM.read(1));
     Serial.println(EEPROM.read(2));
     Serial.println(EEPROM.read(3));


    }
    if (vvod ==  Serial.println(EEPROM.read(0))*1000+Serial.println(EEPROM.read(1))*100+Serial.println(EEPROM.read(2))*10+Serial.println(EEPROM.read(3)) - 1) {
     digitalWrite(rele,1);
     tone(11, 251);
     delay(3000);
    }
  else{
    lcd.clear();
    lcd.setCursor(1, 0);
    lcd.print("Password Error");
  }
    noTone(11);
    delay(2000);
    x = 0;
    lcd.clear(); 
    digitalWrite(rele,0);
    setup();
  }
}