Originariamente inviato da oregon
Sistema il codice che così non si capisce nulla ...

E poi, in

Mqsort(lineptr, 0, nstr );

nstr

da dove viene?



codice:

                                 #include <stdio.h>
                                #include <string.h>
                                 #include <stdlib.h>
                                 #define MAXLINES 1000
                                  #define ALLOCSIZE 10000
                                    #define MAXLEN 1000



                           char *lineptr[MAXLINES]; /* puntatore alle linee di testo */
                           int readlines(char lineptr[], int nlines);
                           void writelines(char *lineptr[], int nlines);
                           void Mqsort (char *lineptr[], int left, int right);
                            int Mgetline(char s[], int lim );
                            void Mswap (char *v[], int i, int j);

 

    int main() 
 
                      
{


                     int nlines ;
                   if ((nlines = readlines(lineptr, MAXLINES)) >= 0 )

{
 
                 Mqsort(lineptr, 0, nstr );
                 writelines(lineptr, nlines);
                 return 0 ;
}

            else
{
           printf("errore: troppe linee di input da ordinare\n");
          return 1 ;
}

}


         int readlines(char *lineptr[], int maxlines ) 
{

       int len;
       int nlines = 0;
       char *p;
       int nstr ;
       char line[MAXLEN];

        while ((len = Mgetline(line,MAXLEN)) > 0 )
       if (nlines >= maxlines || (p = malloc(len)) == NULL)
       return -1 ;

       else

{

           line[len-1] = '\0';
           strcpy(p, line);
           lineptr[nlines++] = p;
           nstr = nlines ;
}

}



        /* getline: carica una linea in s, ritorna la lunghezza */

 int Mgetline(char s[], int lim )   

              
{
            int c, i;
            i= 0;

            while (--lim > 0 && (c = getchar()) != EOF && c != '\n')

           s[i++] = c ;

          if (c == '\n')
             s[i++] = c;
            s[i] = '\0';
             return i;
}



/* qsort : ordina v[left] ... v[right] in ordine crescente */

 

  void Mqsort( char *v[], int left, int right )   

{
              int i, last;
              int nlines;
            
              if (left >= right)  
                 return;   

              Mswap(v, left, (left + right) / 2 );
               last = left;

               for (i= left+1; i <= right; i++)

               if (strcmp (v[i] , v[left]) < 0 )

              Mswap(v, ++last, i);
 
              Mswap(v, left, last);
              Mqsort(v, left, last - 1);
              Mqsort(v, last + 1, right);

}


        /* swap : scambia v[i] con v[j] */

    void Mswap (char *v[], int i, int j) 


{
                   char *temp;

                   temp = v[i];
                    v[i] = v[j];
                    v[j] = temp;

}



            /* writelones scrive in output le linee */


    void writelines(char *lineptr[], int nlines)   

{

               int i;

                 for (i = 0; i < nlines; i++ )
                 printf("%s\n", lineptr[i]);


}