#include <Keypad.h> // kutubxona
const byte satr = 4; // 4 satr
const byte ustun = 4; // 4 ustun
char keys[satr][ustun] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}}; 
byte satrPins[satr] = {9, 8, 7, 6}; 
byte ustunPins[ustun] = {5, 4, 3, 2}; 
String kod = "";
int count = 0; // urinishlar soni
Keypad keypad = Keypad( makeKeymap(keys), satrPins, ustunPins, satr, ustun );
void setup(){
  pinMode(11, OUTPUT); // sariq
  pinMode(12, OUTPUT); //qizil
  pinMode(13, OUTPUT); // yashil
  Serial.begin(9600);
}
void loop(){
  char key = keypad.getKey();
  if (key) {
    kod += key;
    Serial.println(kod);
    if(kod == "1234") 
        {digitalWrite(13, 1); 
         Serial.println("svetadiod yondi");
         count = 0;
         delay(2000);
         digitalWrite(13, LOW);}
    if(kod.length() == 4 && kod != "1234" && count != 3) {
      count++;
      digitalWrite(12, HIGH);
      Serial.println(count);
      digitalWrite(13, 0);
      delay(1000);
      digitalWrite(12, LOW);
    }

    if(count >= 3){
      digitalWrite(11, HIGH);
      Serial.println("Blokka tushdi");
      delay(10000);
      digitalWrite(11, LOW);
    }
    if(kod.length() > 3)
        kod = "";
    }
  }