build

chapter_hashing/hash_algorithm.md

@@ -459,13 +459,53 @@ index = hash(key) % capacity
 === "Rust"
 
     ```rust title="simple_hash.rs"
-    [class]{}-[func]{add_hash}
+    /* 加法哈希 */
+    fn add_hash(key: &str) -> i32 {
+        let mut hash = 0_i64;
+        const MODULUS: i64 = 1000000007;
 
-    [class]{}-[func]{mul_hash}
+        for c in key.chars() {
+            hash = (hash + c as i64) % MODULUS;
+        }
 
-    [class]{}-[func]{xor_hash}
+        hash as i32
+    } 
 
-    [class]{}-[func]{rot_hash}
+    /* 乘法哈希 */
+    fn mul_hash(key: &str) -> i32 {
+        let mut hash = 0_i64;
+        const MODULUS: i64 = 1000000007;
+
+        for c in key.chars() {
+            hash = (31 * hash + c as i64) % MODULUS;
+        }
+
+        hash as i32
+    }
+
+    /* 异或哈希 */
+    fn xor_hash(key: &str) -> i32 {
+        let mut hash = 0_i64;
+        const MODULUS: i64 = 1000000007;
+
+        for c in key.chars() {
+            hash ^= c as i64;
+        }
+
+        (hash & MODULUS) as i32
+    }
+
+    /* 旋转哈希 */
+    fn rot_hash(key: &str) -> i32 {
+        let mut hash = 0_i64;
+        const MODULUS: i64 = 1000000007;
+
+        for c in key.chars() {
+            hash = ((hash << 4) ^ (hash >> 28) ^ c as i64) % MODULUS;
+        }
+
+        hash as i32
+    }
     ```
 
 === "C"

chapter_hashing/hash_collision.md

@@ -1149,7 +1149,179 @@ comments: true
 === "C"
 
     ```c title="hash_map_chaining.c"
-    [class]{hashMapChaining}-[func]{}
+    /* 基于数组简易实现的链式地址哈希表 */
+    struct hashMapChaining {
+        int size;         // 键值对数量
+        int capacity;     // 哈希表容量
+        double loadThres; // 触发扩容的负载因子阈值
+        int extendRatio;  // 扩容倍数
+        Pair *buckets;    // 桶数组
+    };
+
+    typedef struct hashMapChaining hashMapChaining;
+
+    /* 初始化桶数组 */
+    hashMapChaining *newHashMapChaining() {
+        // 为哈希表分配空间
+        int tableSize = 4;
+        hashMapChaining *hashmap = (hashMapChaining *)malloc(sizeof(hashMapChaining));
+
+        // 初始化数组
+        hashmap->buckets = (Pair *)malloc(sizeof(Pair) * tableSize);
+        memset(hashmap->buckets, 0, sizeof(Pair) * tableSize);
+
+        hashmap->capacity = tableSize;
+        hashmap->size = 0;
+        hashmap->extendRatio = 2;
+        hashmap->loadThres = 2.0 / 3;
+
+        return hashmap;
+    }
+
+    /* 销毁哈希表 */
+    void delHashMapChaining(hashMapChaining *hashmap) {
+        for (int i = 0; i < hashmap->capacity; i++) {
+            Pair *pair = &hashmap->buckets[i];
+            Node *node = pair->node;
+            while (node != NULL) {
+                Node *temp = node;
+                node = node->next;
+                free(temp->val);
+                free(temp);
+            }
+        }
+        free(hashmap->buckets);
+        free(hashmap);
+    }
+
+    /* 哈希函数 */
+    int hashFunc(hashMapChaining *hashmap, const int key) {
+        return key % hashmap->capacity;
+    }
+
+    /* 负载因子 */
+    double loadFactor(hashMapChaining *hashmap) {
+        return (double)hashmap->size / (double)hashmap->capacity;
+    }
+
+    /* 添加操作 */
+    void put(hashMapChaining *hashmap, const int key, char *val) {
+        if (loadFactor(hashmap) > hashmap->loadThres) {
+            extend(hashmap);
+        }
+        int index = hashFunc(hashmap, key);
+
+        // 先为新节点分配空间再赋值
+        Node *newNode = (Node *)malloc(sizeof(Node));
+        memset(newNode, 0, sizeof(Node));
+        newNode->key = key;
+        newNode->val = (char *)malloc(strlen(val) + 1);
+        strcpy(newNode->val, val);
+        newNode->val[strlen(val)] = '\0';
+
+        Pair *pair = &hashmap->buckets[index];
+        Node *node = pair->node;
+        if (node == NULL) {
+            hashmap->buckets[index].node = newNode;
+            hashmap->size++;
+            return;
+        }
+        while (node != NULL) {
+            if (node->key == key) {
+                // 释放先前分配的内存
+                free(node->val);
+                // 更新节点的值
+                node->val = (char *)malloc(strlen(val) + 1);
+                strcpy(node->val, val);
+                node->val[strlen(val)] = '\0';
+                return;
+            }
+            if (node->next == NULL) {
+                break;
+            }
+            node = node->next;
+        }
+        node->next = newNode;
+        hashmap->size++;
+    }
+
+    /* 删除操作 */
+    void removeItem(hashMapChaining *hashmap, int key) {
+        int index = hashFunc(hashmap, key);
+        Pair *pair = &hashmap->buckets[index];
+        Node *node = pair->node;
+        // 保存后继的节点
+        Node *prev = NULL;
+        while (node != NULL) {
+            if (node->key == key) {
+                // 如果要删除的节点是桶的第一个节点
+                if (prev == NULL) {
+                    pair->node = node->next;
+                } else {
+                    prev->next = node->next;
+                }
+                // 释放内存
+                free(node->val);
+                free(node);
+                hashmap->size--;
+                return;
+            }
+            prev = node;
+            node = node->next;
+        }
+        return;
+    }
+
+    /* 扩容哈希表 */
+    void extend(hashMapChaining *hashmap) {
+        // 暂存原哈希表
+        Pair *oldBuckets = hashmap->buckets;
+        int oldCapacity = hashmap->capacity;
+
+        // 创建新的哈希表，重新分配一段空间
+        hashmap->capacity *= hashmap->extendRatio;
+        hashmap->buckets = (Pair *)malloc(sizeof(Pair) * hashmap->capacity);
+        memset(hashmap->buckets, 0, sizeof(Pair) * hashmap->capacity);
+        hashmap->size = 0;
+
+        // 将原哈希表中的键值对重新哈希到新的哈希表中
+        for (int i = 0; i < oldCapacity; i++) {
+            Node *node = oldBuckets[i].node;
+            while (node != NULL) {
+                put(hashmap, node->key, node->val);
+                node = node->next;
+            }
+        }
+
+        // 释放原哈希表的内存
+        for (int i = 0; i < oldCapacity; i++) {
+            Node *node = oldBuckets[i].node;
+            while (node != NULL) {
+                Node *temp = node;
+                node = node->next;
+                free(temp->val);
+                free(temp);
+            }
+        }
+        free(oldBuckets);
+    }
+
+    /* 打印哈希表 */
+    void print(hashMapChaining *hashmap) {
+        for (int i = 0; i < hashmap->capacity; i++) {
+            printf("[");
+            Pair *pair = &hashmap->buckets[i];
+            Node *node = pair->node;
+            while (node != NULL) {
+                if (node->val != NULL) {
+                    printf("%d->%s, ", node->key, node->val);
+                }
+                node = node->next;
+            }
+            printf("]\n");
+        }
+        return;
+    }
     ```
 
 === "Zig"