#include <Keypad.h>
#include <ezBuzzer.h>

const int BUZZER_PIN = 11;
const int ROW_NUM    = 4; // four rows
const int COLUMN_NUM = 4; // four columns

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

byte pin_rows[ROW_NUM] = {9, 8, 7, 6};      // connect to the row pinouts of the keypad
byte pin_column[COLUMN_NUM] = {5, 4, 3, 2}; // connect to the column pinouts of the keypad

Keypad keypad = Keypad(makeKeymap(keys), pin_rows, pin_column, ROW_NUM, COLUMN_NUM );
ezBuzzer buzzer(BUZZER_PIN); // create ezBuzzer object that attach to a pin;

void setup() {
  Serial.begin(9600);
}

void loop() {
  buzzer.loop(); // MUST call the buzzer.loop() function in loop()
  char key = keypad.getKey();

  if (key) {
    if (key == '1')
    delay(1000);
     if (key == '2')
    delay(2000);
     if (key == '3')
    delay(3000);
     if (key == '4')
    delay(4000);
     if (key == '5')
    delay(5000);
     if (key == '6')
    delay(6000);
     if (key == '7')
    delay(7000);
     if (key == '8')
    delay(8000);
     if (key == '9')
    delay(9000); 
     if (key == '10')
    delay(10000);

    Serial.print(key); // prints key to serial monitor
    buzzer.beep(100);  // generates a 100ms beep
  }
}