#include <Keypad.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

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

int l = 0;
int nRow = 0;

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

Keypad keypad = Keypad(makeKeymap(keys), ROWS, COLS, 4,4);
LiquidCrystal_I2C lcd(0x27, 16,2);

void setup() {
  lcd.init();                      // initialize the lcd
  // Print a message to the LCD.
  lcd.backlight();
  lcd.setCursor(1,0);
  lcd.print("Hello Arduino!");
  Serial.begin(9600);
  delay(1500);
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print(">>introductions>");
  delay(1000);
  lcd.setCursor(0,1);
  lcd.print("*press# to clear"); 
  delay(2500);
  lcd.clear();
  delay(1000);
}

void loop() {
  char key = keypad.getKey();
  int i = +1;

  if (key != NO_KEY){
    Serial.print("Entered number = ");
    if (key == '#') {
      Serial.print("Clear the LCD");
    }
    Serial.println(key);
    lcd.print(key);
    l+= 1;
    if (l>15 and nRow==0)
  {
    lcd.setCursor(0, 1);
    nRow=1;
  }
   	if (l>32)
    {    
    lcd.clear();
    lcd.setCursor(0,0);
	  l=0;
    nRow=0;
    }

     if (key == '#') {
      lcd.clear();
    }

  }
}