#include <Keypad.h>
#include <LiquidCrystal_I2C.h>

const uint8_t ROWS = 4;
const uint8_t COLS = 4;
char pass[4] = {'3', '0', '0', '1'}; 
char keys[ROWS][COLS] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};
byte x = 0;
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);
LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  Serial.begin(9600);
  lcd.backlight();
  lcd.init();
  lcd.setCursor(1, 0);
  lcd.print("Enter Password");

}

void loop() {
  char key = keypad.getKey();
  if (key != NO_KEY) {
    Serial.println(key);
    lcd.setCursor(x, 1);
    lcd.print(key);
    x++;

  }
  if(x > 3) {
    lcd.clear();
    lcd.setCursor(1, 0);
    lcd.print("Password Error");
    delay(2000);
    lcd.setCursor(1, 0);
    lcd.print("Enter Password");
    x = 0;
  }
    if(key = pass) {
    lcd.setCursor(5, 1);
    lcd.print("Welcome!");
    delay(2000);
    lcd.print("Enter Password");

}
}