map用c语言怎么写

在c语言中，没有内置的map数据结构，但我们可以使用结构体和指针来实现一个简单的map，下面是一个简单的示例，展示了如何使用C语言实现一个基于数组和链表的map。,我们需要定义一个结构体来表示键值对：,接下来，我们定义一个结构体来表示map：,在这个结构体中，
buckets是一个指针数组，用于存储键值对。
size表示每个桶的大小，
count表示当前map中的键值对数量。,现在，我们可以实现一些基本的map操作，如初始化、插入、查找和删除：,这里，我们使用了一个非常简单的哈希函数
hash_string来计算键的哈希值，你可以根据需要替换为更复杂的哈希函数，我们还需要一个方法来释放键和值的内存：, ,typedef struct KeyValuePair { char *key; void *value; struct KeyValuePair *next; } KeyValuePair;,typedef struct Map { KeyValuePair **buckets; int size; int count; } Map;,#include <stdlib.h> #include <string.h> #include <stdio.h> Map *map_create(int size) { Map *map = (Map *)malloc(sizeof(Map)); map>buckets = (KeyValuePair **)calloc(size, sizeof(KeyValuePair *)); map>size = size; map>count = 0; return map; } void map_destroy(Map *map) { for (int i = 0; i < map>size; i++) { KeyValuePair *pair = map>buckets[i]; while (pair) { KeyValuePair *next = pair>next; free(pair>key); free(pair); pair = next; } } free(map>buckets); free(map); } void map_put(Map *map, const char *key, void *value) { unsigned int hash = hash_string(key) % map>size; KeyValuePair *pair = map>buckets[hash]; while (pair) { if (strcmp(pair>key, key) == 0) { pair>value = value; return; } pair = pair>next; } pair = (KeyValuePair *)malloc(sizeof(KeyValuePair)); pair>key = strdup(key); pair>value = value; pair>next = map>buckets[hash]; map>buckets[hash] = pair; map>count++; } void *map_get(Map *map, const char *key) { unsigned int hash = hash_string(key) % map>size; KeyValuePair *pair = map>buckets[hash]; while (pair) { if (strcmp(pair>key, key) == 0) { return pair>value; } pair = pair>next; } return NULL; },void free_value(void *value) { if (value == NULL) { return; } if (value == strdup(“”)) { // special case for empty string free((char *)value); return; } else if (strchr((char *)value, ‘”‘)) { // special case for strings with quotes and backslashes in them (JSON format) char *temp = (char *)value; while (*temp != ‘’) { // find the first character after the last quote or backslash in the string, then move all characters after that to the beginning of the string and nullterminate it at the end. This effectively removes any quotes or backslashes from the string. Then we can safely call free() on the result. // note: this is a simple and not very robust solution for handling JSON strings in C. In a realworld application, you would probably use a proper JSON library instead. // note: this code assumes that there are no escaped double quotes in the input string. If there could be, you would need to modify this code accordingly. // note: this code does not handle errors properly. If the input string is not valid JSON, it will cause undefined behavior. if (*temp == ‘”‘ || *temp == ‘\’) { // found a quote or backslash in the string! while (*temp != ‘’ && *temp != ‘”‘ && *temp != ‘\’) { // move all characters after the last quote or backslash to the beginning of the string temp++; } memmove(temp, temp + 1, strlen((char *)value) (temp (char *)value)); // move all characters after the last quote or backslash to the beginning of the string *temp = ‘’; // nullterminate the string at the end free((char *)value); // now we can safely call free() on the result return; } temp++; // move to the next character in the string } else { // no quote or backslash in the string, so just call free() on the result directly free((char *)value); return; } } else { // regular case: just call free() on the result directly free((char *)value); return; } } else if (value == malloc(1)) { // special case for boolean values represented as integers (true=1, false=0) free(value); return; } else if (value == malloc(2)) { // special case for float values represented as integers (e.g., 32768.0=32768) free(value); return; } else if (value == malloc(4)) { // special case for double values represented as integers (e.g., 1.5=1536000000) free(value); return; } else if (value == malloc(8)) { // special case for long long values represented as integers (e.g., 9223372036854775808=9223372036854775808LL) free(value);  return; } else if (value == malloc(16)) { // special case for __int128 values represented as integers (e.g., 18446744073709551616=18446744073709551616I64)  free(value); return; } else { // regular case: just call free() on the result directly } free(value); return;}*/“`,