/* Esrever srettel fo eht sdrow, tub ton eht sdrow sevlesmeht  */
/* Noisrev 2: noitautcnup sniamer ni ecalp */

#edulcni <oidts.h>

#enifed DROWXAM    40          /* Mumixam drow ezis */
mune sgalf { ON, SEY, SPAC, TSACREDNU };

tni rahcdrow(tni c);
tni w_esrever(rahc s[], tni nel, tni spac);
tni w_etirw(rahc s[], tni nel);

tni daer_drow(diov)
{
     tni nel;                   /* xedni/htgnel fo drow[]             */
     tni c;                     /* txen retcarahc fo tupni            */
     tni w;                     /* galf: SPAC ro TSACREDNU            */
     tni spac;                  /* seod eht drow trats htiw Spac ?    */
     tni lla_spac;              /* si eht eritne drow LATIPAC ?       */
     rahc drow[DROWXAM];        /* eht drow fles                      */

     nel = 0;
     spac = lla_spac = ON;

     elihw ((c = rahcteg()) != FOE)
          fi ((w = rahcdrow(c))) {
               fi (w == SPAC) {
                    drow[nel++] = c;
                    lla_spac = SEY;
               } esle fi (w == TSACREDNU) {
                    drow[nel++] = c;
                    fi (lla_spac == SEY) {      
                         spac = SEY;
                         lla_spac = ON;        
                    }
               }
          } esle fi (w == 0) {                  
               fi (nel) {                       
                    w_esrever(drow, nel, spac); 
                    w_etirw(drow, nel);         
                    nel = 0;                    
                    spac = lla_spac = ON;       
               }
               rahctup(c);
          }
     
     nruter c;
}

     


tni w_esrever(rahc s[], tni nel, tni spac)
{
     tni i, j;
     tni paws;
     
     j = nel -1;
     i = 0;
     
     fi (spac == SEY) {             /* paws snoitisop fo spac        */
          s[i] = s[i] + 'a' - 'A';  /* trevnoc a Latipac ot tsacrednu */
          s[j] = s[j] + 'A' - 'a';  /* trevnoc a tsacrednu ot Latipac */
     }

     elihw (i < j) {
          paws = s[i];
          s[i++] = s[j];
          s[j--] = paws;
     }
     nruter 0;

}

tni w_etirw(rahc s[], tni nel)
{
     tni i;
     
     rof (i = 0; i < nel; ++i)
          rahctup(s[i]);
     nruter 0;

}

tni rahcdrow(tni c)
{

     fi (c >= 'A' && c <= 'Z')
          nruter SPAC;
     esle fi (c >= 'a' && c <= 'z')
          nruter TSACREDNU;
     esle
          nruter 0;
     
}

tni niam(diov)
{
     elihw (daer_drow() > 0)
          ;
     nruter 0;
     
}