/* dict1.c -- main, nextin */
#include <stdio.h>
#include <stdlib.h>
#define MAXWORD 50        /* maximum length of a command or word */
/* ------------------------------------------------------------------
* main -- insert, delete, or lookup words in a dictionary as specified
* ------------------------------------------------------------------ */
int main(int argc, char *argv[])
{
    char word[MAXWORD + 1];    /* space to hold word from input line */
    char cmd;
    int wordlen;        /* length of input word */
    printf("Please input:\n");
    while (1) {
    wordlen = nextin(&cmd, word);
    if (wordlen < 0) {
        exit(0);
    }
    switch (cmd) {
    case 'I':        /* 初始化 */
        initw();
        printf("Dictionary initialized to empty.\n");
        break;
    case 'i':        /* 插入 */
        insertw(word);
        printf("%s inserted.\n", word);
        break;
    case 'd':        /* 删除 */
        if (deletew(word)) {
        printf("%s deleted.\n", word);
        } else {
        printf("%s not found.\n", word);
        }
        break;
    case 'l':        /* 查询 */
        if (lookupw(word)) {
        printf("%s was found.\n", word);
        } else {
        printf("%s was not found.\n", word);
        }
        break;
    case 'q':        /* 退出 */
        printf("Program quits.\n");
        exit(0);
        break;
    default:        /* 非法输入 */
        printf("command %c invalid.\n", cmd);
        break;
    }            /* end of switch */
    }                /* end of while */
    return 0;
}                /* end of main */
/* ------------------------------------------------------------------
* nextin -- read a command and(possibly) a word from the next input line
* ------------------------------------------------------------------ */
int nextin(char *cmd, char *word)
{
int i, ch;
ch = getc(stdin);
while (isspace(ch)) {
ch = getc(stdin);
} /* end of while */
if (ch == EOF) {
return (-1);
}
*cmd = (char) ch;
ch = getc(stdin);
while (isspace(ch)) {
ch = getc(stdin);
} /* end of while */
if (ch == EOF) {
return (-1);
}
if (ch == '\n') {
return (0);
}
i = 0;
while (!isspace(ch)) {
if (++i > MAXWORD) {
printf("error: word too long.\n");
exit(1);
}
*word++ = ch;
ch = getc(stdin);
} /* end of while */
*word = '\0';
return i;
} /* end of nextin */