convern.h

// ôóíêöèÿ ditobi() - Decrimal Integer To Binary Integer ïåðåâîäèò öåëîå ÷èñëî,
// çàäàííîå â 10-é ôîðìå, â öåëîå 2-å ÷èñëî. ïàðàìåòð num - öåëîå 10-å ÷èñëî
// äëÿ ïðåîáðàçîâàíèÿ. ïàðàìåòð s - óêàçàòåëü íà ñòðîêó ñ öåëûì 2-é ÷èñëîì.
void ditobi( int num, char* s )
{
   int i = 0;
   if ( num )
     for( ; num!= 0; i++ )
     {
         if( num % 2 )
            s[i] = '1';
         else
            s[i] = '0';
         num/= 2;
     }
   else
      s[i++] = '0';
   s[i] = '\0';
}

// ôóíêöèÿ exchs() - Exchange String ïåðåïèñûâàåò ñòðîêó çàäîì íà ïåðåä.
// ïàðàìåòð str - ñòðîêà, äëÿ îáðàáîòêè.
void exchs( char *str )
{
   int j, i = strlen( str ) - 1;
   char sBuf[33], *s = sBuf;

   for( j = 0; i > -1; j++, i-- )
      s[j] = str[i];

   s[j] = '\0';
   sprintf( str, "%s", s );
}

// ôóíêöèÿ äîáàâëÿåò( óáèðàåò ) íóëè, ÷òîáû ñòðîêà áûëà äëèíîé â noe.
void AddZero( char* s, int noe )
{
   char sBuf[80], *buf = sBuf;
   int i, k = 0, j = strlen( s );

   if( j > noe )
   {
      for( i = strlen( s )-1; k < noe; i--, k++ )
         buf[k] = s[i];

      buf[k] = '\0';
      exchs( buf );
      sprintf( s, "%s", buf );
      return ;
   }
   else
      if( j == noe )
         return ;

   sprintf( buf, "%s", s );
   j = noe - j;
   for( i = 0; i < j;  i++ )
      s[i] = '0';

   s[i] = '\0';
   strcat( s, buf );
}