#include <LiquidCrystal.h>
LiquidCrystal lcd(13,12,11,10,9,8,7,6,5,4);

void setup() {
  // put your setup code here, to run once:
  lcd.begin(16,2);
  lcd.setCursor(0,0);
}

void loop() {
  // put your main code here, to run repeatedly:
  int hr,mins,secs;
  for(hr=0;hr<24;hr++)
  {
   for(mins=0;mins<60;mins++)
   {
    for(secs=0;secs<60;secs++)
    {
      lcd.setCursor(0,0);
      lcd.print(hr);
      lcd.print(':');
      lcd.print(mins);
      lcd.print(':');
      lcd.print(secs);
      delay(981);
    }
   }
  }
}