A hash function h(key) maps a key (often a string or integer) to an integer in the range [0, size-1] , where size is the capacity of the hash table.
create_node() allocates memory for the Node structure and duplicates the key string using malloc and strcpy . It sets the value and the next pointer to NULL . If any allocation fails, the program prints an error and exits.
Will your dictionary manage (e.g., over 100,000 items)?
| Method | Description | Pros | Cons | |--------|-------------|------|------| | | Each bucket points to a linked list of entries | Simple, no limit on entries | Extra memory for pointers | | Open Addressing | Probe sequentially for next free slot | Cache-friendly, no pointers | Table can fill up, deletion is tricky |
prev = curr; curr = curr->next;
The following complete program implements a dictionary with string keys and integer values. It handles dynamic memory allocation, collision resolution via chaining, and proper memory cleanup.
curr = curr->next;
return hash;
If used in a multi‑threaded environment, add mutex locks around operations that modify the table. c program to implement dictionary using hashing algorithms
To implement a dictionary in C using hashing, you essentially build a that maps string keys to specific values . Since C lacks a built-in dictionary type, you must manage memory and collisions manually. 1. Core Components
Therefore, our implementation will use with singly linked lists.
. Choosing a strong hash function like DJB2 and maintaining a large bucket array keeps operations running at efficiency.
: Defining the key-value node and the main hash table array. A hash function h(key) maps a key (often
For this article, we'll implement because it is easier to understand and works reliably under high load.
Common probe methods:
return d;