#include <Keypad.h>

const byte ROWS = 4; //four rows
const byte COLS = 4; //three columns
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};
byte rowPins[ROWS] = {5, 4, 3, 2}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {9, 8, 7, 6}; //connect to the column pinouts of the keypad


int digit[4];
int num =0;

Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );

void setup(){
  Serial.begin(9600);
}
  
void loop(){
  char key = keypad.getKey();
  
  if (key){
    digit[num] = key - 48;
    num = num+1;
    if(num>3){
      Serial.print(digit[0]);
      Serial.print(" ");
      Serial.print(digit[1]);\
      Serial.print(" ");
      Serial.print(digit[2]);
      Serial.print(" ");
      Serial.print(digit[3]);
      num =0;

      if(digit[0]==1 && digit[1]==1 && digit[2]==1 && digit[3]==1){
        Serial.println("      UNLOCK");
        
      }
      else{
        Serial.println("        LOCK");
      }
    }
  }
}