: When two words yield the same index, the newer node is pushed onto the front of that bucket's linked list. This takes
-------------------------------------------------------------*/ int dict_delete(Dict *d, const char *key) unsigned int idx = hash(key, d->size); Node *curr = d->table[idx]; Node *prev = NULL;
int main() // Create dictionary with custom table size Dictionary *dict = dict_create(TABLE_SIZE); if (!dict) printf("Failed to create dictionary\n"); return 1;
#include <stdio.h> #include <stdlib.h> #include <string.h> c program to implement dictionary using hashing algorithms
#define DEFAULT_SIZE 101 /* Prime number for better distribution */
In C, a chaining-based dictionary might define nodes as:
for (int i = 0; i < old_size; i++) Entry *curr = old_buckets[i]; while (curr) dict_put(dict, curr->key, curr->value); Entry *tmp = curr; curr = curr->next; free(tmp); : When two words yield the same index,
Below is a skeletal C implementation demonstrating the core operations:
Common probe methods:
Deleting a key involves searching the chain while keeping track of the previous entry. If found, we unlink it and free its memory. Because the number of possible keys usually exceeds
Because the number of possible keys usually exceeds the size of the array, different keys may occasionally produce the exact same hash index. This is called a .
If used in a multi‑threaded environment, add mutex locks around operations that modify the table.
typedef struct Entry char *key; int value; struct Entry *next; Entry;
strdup is POSIX but not part of standard C. On systems lacking it, you can implement your own: char *dup = malloc(strlen(key)+1); strcpy(dup, key); .
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