程序代码：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
struct word {
    char * words;
    struct word * p_word;
};
struct word_tab {
    char alphaber;
    struct word_tab * total;
    struct word * word;
};
int index_word_tab(struct word_tab ** p_total, char word[]);
void print_word(struct word_tab ** p_total);
int getword(char word[],int n);


int main(void)
{
    struct word_tab *p;
    struct word_tab **kp;
    char word1[50];

    p = NULL;
    kp = &p;

    while(getword(word1,50) > 0)
        index_word_tab(kp, word1);

    print_word(kp);

    getchar();
    return 0;
}

int getword(char word[], int n)
{
    int i,c;

    for(i = 0; i < n - 1 && (c = getchar()) != EOF && !isspace(c);i++)
        word[i] = c;

    word[i] = '\0';

    return i;
}


int index_word_tab(struct word_tab ** p_total, char word[])
{
    int determine(char word[]);
    struct word_tab * next;
    struct word_tab * new_total;
    struct word * next_word;
    struct word * new_word;
    struct word ** kp_word;
    char w;

    if(determine(word) < 0)
    {
        printf("ERORR: %s\n",word);
        return 0;
    }
    w = tolower(word[0]);

    while((next = *p_total) != NULL && next->alphaber < w)                                                         
        p_total = &next->total;

    if(next == NULL || next->alphaber != w)
    {
        new_total = (struct word_tab *)malloc(sizeof(struct word_tab));
        if (new_total == NULL)
            return 0;
        *p_total = new_total;
        new_total->total = next;
        new_total->alphaber = w;
        new_total->word = NULL;
    }

    kp_word = &(*p_total)->word;

    while ((next_word = *kp_word) != NULL && strcmp(next_word->words, word) <= 0)
    {
        if (strcmp(next_word->words, word) == 0)
            return 0;
        kp_word = &next_word->p_word;
    }

    new_word = (struct word *)malloc(sizeof(struct word));
    if (new_word == NULL)
        return 0;
    *kp_word = new_word;
    new_word->p_word = next_word;
    new_word->words = strdup(word);

    return 1;
}


void print_word(struct word_tab ** p_total)
{
    struct word_tab * next;
    struct word * word_next;
    int i;

    while((next = *p_total) != NULL)
    {
        for(word_next = next->word,i = 0; word_next != NULL;word_next = word_next->p_word,i++)
            printf("%s%c", word_next->words,((i+1)%8)?' ':'\n');
        printf("\n\n");
        p_total = &next->total;
    }
}


int determine(char word[])
{
    int i,j;
    j = strlen(word);
   
    for(i = 0; isalpha(word[i]);i++)
      ;

    if(i == j)
        return i;
    else
        return -1;
}

[此贴子已经被作者于2017-2-18 11:42编辑过]