#include <Keypad.h>

const byte ROWS = 4;
const byte COLS = 4;
const int led = 10;

//char code[4] = {'4','0','9','9'};
//char pass[4] = {};

String code = "4099";
String pass = "";

char hexakeys[ROWS][COLS]={
{'1','2','3','A'},
{'4','5','6','B'},
{'7','8','9','C'},
{'*','0','#','D'}
};

byte rowPins[ROWS] = {9,8,7,6};
byte colPins[COLS] = {5,4,3,2};

Keypad customkeypad = Keypad( makeKeymap(hexakeys),rowPins,colPins, ROWS, COLS);


void setup() {
  Serial.begin(9600);
  pinMode(led, OUTPUT);
  digitalWrite(led, HIGH);
  delay(100);
  digitalWrite(led, LOW);
  delay(100);
  digitalWrite(led, HIGH);
  delay(100);
  digitalWrite(led, LOW);
  delay(100);
  digitalWrite(led, HIGH);
  delay(100);
  digitalWrite(led, LOW);
  delay(100);
}

void loop() {

  pinMode(led, OUTPUT);
  char a = 0;
  int i = 0;
  char in = customkeypad.getKey();

 if(in){
   digitalWrite(led, HIGH);
   delay(100);
   digitalWrite(led, LOW);
   Serial.write(in);

   if (pass.length() <= 4) {
     pass += in;
   }
   if (pass.length() == 4) {
     if (pass == code) {
        Serial.print("DANK\n");
     } else {
        Serial.print("NOT DANK\n");
     }
     pass = "";
   }
 }
}