GPS Clock Arduino - Arduino for beginners

#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);  // set the LCD address to 0x27 for a 16 chars and 2 line display > 0x3F in my case for a 2004 lcd display
#include <Adafruit_GPS.h>
#include <SoftwareSerial.h>
// Connect the GPS Power pin to 5V
// Connect the GPS Ground pin to ground
// Connect the GPS TX (transmit) pin to Digital 4
// Connect the GPS RX (receive) pin to Digital 3
SoftwareSerial mySerial(4, 3);
Adafruit_GPS GPS(&mySerial);
#define GPSECHO  true

int timezone = +2; // select your time zone

void setup()
{
  lcd.init();
  lcd.backlight();
  lcd.setCursor(4,0);
  lcd.print("GPS clock");
  lcd.setCursor(0,1);
  lcd.print("Levente Daradici");
  delay(5000);
  lcd.clear();
  GPS.begin(9600);
  GPS.sendCommand(PMTK_SET_NMEA_OUTPUT_RMCGGA);
  GPS.sendCommand(PMTK_SET_NMEA_UPDATE_1HZ);
  GPS.sendCommand(PGCMD_ANTENNA);
  delay(1000);
}

uint32_t timer = millis();
void loop()
{
  char c = GPS.read();
  if ((c) && (GPSECHO))
  if (GPS.newNMEAreceived())
      {
        if (!GPS.parse(GPS.lastNMEA()))
      return;
      }

  if (timer > millis())  timer = millis();

  if (millis() - timer > 1000) {
    timer = millis();

    lcd.setCursor(4,0);
    int hour = (GPS.hour) + timezone;
        if (hour < 10) { lcd.print('0'); }
        lcd.print(hour, DEC); lcd.print(':');
        if (GPS.minute < 10) { lcd.print('0'); }
        lcd.print(GPS.minute, DEC); lcd.print(':');
        if (GPS.seconds < 10) { lcd.print('0'); }
        lcd.print(GPS.seconds, DEC);

    lcd.setCursor(3,1);
        if (GPS.day < 10) { lcd.print('0'); }
        lcd.print(GPS.day, DEC); lcd.print('.');
        if (GPS.month < 10) { lcd.print('0'); }
        lcd.print(GPS.month, DEC); lcd.print('.');
        lcd.print("20");
        lcd.print(GPS.year, DEC);

  }
}