A dictionary, also known as a hash table or a map, is a fundamental data structure in computer science that stores a collection of key-value pairs. It allows for efficient retrieval of values by their associated keys. Hashing algorithms are widely used to implement dictionaries, as they provide fast lookup, insertion, and deletion operations.
int main() { HashTable* hashTable = createHashTable(); insert(hashTable, "apple", "fruit"); insert(hashTable, "banana", "fruit"); insert(hashTable, "carrot", "vegetable"); printHashTable(hashTable); char* value = search(hashTable, "banana"); printf("Value for key 'banana': %s\n", value); delete(hashTable, "apple"); printHashTable(hashTable); return 0; } c program to implement dictionary 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; } current = current->next; } return NULL; } A dictionary, also known as a hash table
// Create a new node Node* createNode(char* key, char* value) { Node* node = (Node*) malloc(sizeof(Node)); node->key = (char*) malloc(strlen(key) + 1); strcpy(node->key, key); node->value = (char*) malloc(strlen(value) + 1); strcpy(node->value, value); node->next = NULL; return node; } char* value = search(hashTable