#include <Keypad.h>
const uint8_t ROWS = 4;
const uint8_t COLS = 4;
char keys[ROWS][COLS] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};

uint8_t colPins[COLS] = { 5, 4, 3, 2 };
uint8_t rowPins[ROWS] = { 9, 8, 7, 6 };

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);
const int ledPin1 = 11;

void setup() 
{
  pinMode(ledPin1, OUTPUT);
  Serial.begin(9600);
}

void loop() 
{
  char key = keypad.getKey();

  if (key != NO_KEY) 
  {
    Serial.println(key);
    switch (key) 
    {
      case '1':
        digitalWrite(ledPin1, HIGH);
        break;
      case '0':
        digitalWrite(ledPin1, LOW);
        break;
    }
  }
}