linux下c 编写字典

在Linux下使用C语言编写字典程序，通常涉及到数据结构的选择、文件操作、字符串处理等方面。下面是一个简单的示例，展示如何实现一个基本的字典功能，包括添加单词和查找单词。

基本概念

数据结构：可以使用哈希表（Hash Table）来存储单词及其定义，以实现快速的查找。
文件操作：可以将字典数据存储在文件中，以便持久化。
字符串处理：需要对输入的单词和定义进行字符串处理。

示例代码

以下是一个简单的示例代码，展示如何实现一个基本的字典程序：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX_WORD_LEN 100
#define MAX_DEF_LEN 256
#define TABLE_SIZE 1000

typedef struct {
    char word[MAX_WORD_LEN];
    char definition[MAX_DEF_LEN];
} Entry;

typedef struct {
    Entry *entries[TABLE_SIZE];
} Dictionary;

unsigned int hash(const char *word) {
    unsigned int hash = 0;
    while (*word) {
        hash = (hash << 5) + *word++;
    }
    return hash % TABLE_SIZE;
}

void add_word(Dictionary *dict, const char *word, const char *definition) {
    unsigned int index = hash(word);
    Entry *entry = malloc(sizeof(Entry));
    strcpy(entry->word, word);
    strcpy(entry->definition, definition);
    dict->entries[index] = entry;
}

const char *find_word(Dictionary *dict, const char *word) {
    unsigned int index = hash(word);
    Entry *entry = dict->entries[index];
    if (entry && strcmp(entry->word, word) == 0) {
        return entry->definition;
    }
    return NULL;
}

void free_dictionary(Dictionary *dict) {
    for (int i = 0; i < TABLE_SIZE; i++) {
        if (dict->entries[i]) {
            free(dict->entries[i]);
        }
    }
}

int main() {
    Dictionary dict = {0};
    add_word(&dict, "apple", "A fruit that is sweet and crisp.");
    add_word(&dict, "banana", "A long curved fruit that grows in clusters.");

    const char *definition = find_word(&dict, "apple");
    if (definition) {
        printf("apple: %s\n", definition);
    } else {
        printf("Word not found.\n");
    }

    definition = find_word(&dict, "banana");
    if (definition) {
        printf("banana: %s\n", definition);
    } else {
        printf("Word not found.\n");
    }

    free_dictionary(&dict);
    return 0;
}