#include <time.h>
#include <stdlib.h>
#include <stdio.h>

void wait ( int seconds )
{
clock_t endwait;
endwait = clock () + seconds * CLK_TCK ;
while (clock() < endwait) {}
}

int main()
{
int Ore=0,
    Minuti=0,
    Secondi=0;
    for( ; ; )
    {
      system("cls");
      printf("%2.2d:%2.2d:%2.2d",Ore, Minuti, Secondi);

      do
      {
        system("CLS");
        printf("%2.2d:%2.2d:%2.2d",Ore, Minuti, Secondi);

        do
        {
          system("CLS");
          printf("%2.2d:%2.2d:%2.2d",Ore, Minuti, Secondi);
          wait( 1 );
          Secondi++;
        }
        while(Secondi<60);
        Secondi=0;
        Minuti++;
      }
      while(Minuti<60);
      Minuti=0;
      Ore++;
    }
}