// Importing
#include <Keypad.h>

// Global Variables
const uint8_t r = 4;
const uint8_t c = r;

char keys[r][c] = {
  {"1", "2", "3", "A"},
  {"4", "5", "6", "B"},
  {"7", "8", "9", "C"},
  {"*", "0", "#", "D"}
}

uint8_t rows[r] = {5, 4, 3, 2};
uint8_t cols[c] = {9, 8, 7, 6};

// Defining the keypad
Keypad pad = Keypad(makeKeymap(keys), rows, cols, r, c)


void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);

};

void loop() {
  // put your main code here, to run repeatedly:
  char key = pad.getKey();
  if (key) {
    Serial.print("Key: ");
    Serial.print(key);
    Serial.print(" has been pressed");
    Serial.println();
  }

};