Implementing a dictionary in C using hashing algorithms is a rewarding challenge that teaches fundamental concepts of data structures, memory management, and algorithmic efficiency. The separate chaining approach presented here provides a robust foundation that can be extended with rehashing, generic types, and concurrency support.
void delete(char *key) unsigned long idx = hash(key); Entry *current = table[idx]; Entry *prev = NULL; while (current) if (strcmp(current->key, key) == 0) if (prev) prev->next = current->next; else table[idx] = current->next; free(current->key); free(current); return; c program to implement dictionary using hashing algorithms
// Call this after every insertion void check_and_resize(HashTable **dict) float load = (float)(*dict)->count / (*dict)->size; if (load > 0.75) resize(dict, (*dict)->size * 2); Implementing a dictionary in C using hashing algorithms
// Search for a value by its key char* search(HashTable* hashTable, char* key) int index = hash(key); Node* current = hashTable->buckets[index]; while (current != NULL) if (strcmp(current->key, key) == 0) return current->value; Always test with your actual key distribution before
Remember: The quality of your hash function directly determines the performance of your dictionary. Always test with your actual key distribution before deployment.
: Always apply % table_size to the result to keep the index within bounds.
Entry *hash_table[TABLE_SIZE]; Use code with caution. Copied to clipboard 2. Implement the Hash Function