LCD WITH I2C

This is the error message

Arduino: 1.8.5 (Windows 10), Board: "Arduino/Genuino Uno"

morse_with_lcd:8: error: 'NEGATIVE' was not declared in this scope

 LiquidCrystal_I2C lcd(I2C_ADDR, 2, 1, 0, 4, 5, 6, 7, 3, NEGATIVE);

                                                         ^

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

 };

 ^

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:16:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

                   }; // numbers 0-9

                   ^

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:20:19: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino: In function 'void flashSequence(char*)':

C:\Users\ASUS\Documents\Arduino\morse_with_lcd\morse_with_lcd.ino:71:25: warning: NULL used in arithmetic [-Wpointer-arith]

   while (sequence[i] != NULL)

                         ^

exit status 1
'NEGATIVE' was not declared in this scope

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

now here is the actual code

#include <Wire.h> //libraries of the LCD with I2C
#include <LiquidCrystal.h>
#include <LiquidCrystal_I2C.h>

#define I2C_ADDR 0x27  // Define the address of the serial communication display 
#define LED_OFF 0
#define LED_ON 1
LiquidCrystal_I2C lcd(I2C_ADDR, 2, 1, 0, 4, 5, 6, 7, 3, NEGATIVE);

int ledPin = 8;

char* letters[] = {
  ".-", "-...", "-.-.", "-..", ".", "..-.", "--.", "....", "..", // letters A-I
  ".---", "-.-", ".-..", "--", "-.", "---", ".--.", "--.-", ".-.", // letters J-R
  "...", "-", "..-", "...-", ".--", "-..-", "-.--", "--.." //letters S-Z
};

char* numbers[] = {"-----", ".----", "..---", "...--", "....-", ".....", "-....",
                   "--...", "---..", "----."
                  }; // numbers 0-9

int dotDelay = 200; //Dot time

void setup()
{
  lcd.begin(16, 2);              //Initialize the display
  lcd.setBacklight(LED_OFF);
  lcd.cursor();
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);
}

void loop()
{
  char ch;
  if (Serial.available()) // is there anything to be read from USB?
  {
    ch = Serial.read(); // read a single letter
    if (ch >= 'a' && ch <= 'z')
    {
      flashSequence(letters[ch - 'a']);
      lcd.write(ch);
      delay(1500);
    }
    else if (ch >= 'A' && ch <= 'Z')
    {
      flashSequence(letters[ch - 'A']);
      lcd.write(ch);
      delay(1500);
    }
    else if (ch >= '0' && ch <= '9')
    {
      flashSequence(numbers[ch - '0']);
      lcd.write(ch);
      delay(1500);
    }
    else if (ch == ' ')
    {
      delay(dotDelay * 4); // gap between words
      lcd.write(ch);
      delay(1500);
    }
  }


}

void flashSequence(char* sequence)
{
  int i = 0;
  while (sequence[i] != NULL)
  {
    flashDotOrDash(sequence[i]);
    i++;
  }
  delay(dotDelay * 3); // gap between letters
}

void flashDotOrDash(char dotOrDash)
{
  digitalWrite(ledPin, HIGH);
  if (dotOrDash == '.')
  {
    delay(dotDelay);
  }
  else // must be a -
  {
    delay(dotDelay * 3);
  }
  digitalWrite(ledPin, LOW);
  delay(dotDelay); // gap between flashes
}