C Program To Implement Dictionary Using Hashing Algorithms

dictionary is an abstract data type that maps unique keys to values. Since C lacks a built-in dictionary like Python or C#, you can implement one efficiently using a hash table . This approach provides average constant-time complexity, , for insertion, search, and deletion. 1. Define the Data Structures

unsigned long hash_crc(const char *str) 
    unsigned long hash = 0xFFFFFFFF;
    int c;
    while ((c = *str++)) 
        hash = (hash >> 8) ^ crc32_table[(hash ^ c) & 0xFF];
// djb2 hashing algorithm unsigned int hash(const char *str)  unsigned long hash = 5381; int c; while ((c = *str++))  // hash * 33 + c hash = ((hash << 5) + hash) + c;  return hash % TABLE_SIZE;   Use code with caution. Copied to clipboard 3. Implement Core Operations c program to implement dictionary using hashing algorithms
4.2 Hash Function
unsigned long hash(const char* key, int table_size) 
    unsigned long hash_value = 0;
    int prime = 31;
    while (*key) 
        hash_value = (hash_value * prime) + (*key);
        key++;
Advantages:
// Inserting values
insert(&ht, 1, 100);
insert(&ht, 2, 200);
insert(&ht, 11, 1100); // Collision: 11 % 10 = 1 (chains with key 1)
insert(&ht, 21, 2100); // Collision: 21 % 10 = 1 (chains with key 1 and 11)
insert(&ht, 5, 500);
printf("NULL\n");
unsigned int hash(const char *key, int size)  unsigned int hash_val = 5381; int c; while ((c = *key++)) hash_val = ((hash_val << 5) + hash_val) + c; // djb2: hash * 33 + c return hash_val % size;   Use code with caution. Copied to clipboard Essential Operations dictionary is an abstract data type that maps