unordered_map_example.c

#include <libdsc/unordered_map.h>
#include <stdio.h>
#include <string.h>

// Hash function for strings
static size_t string_hash(void const *key) {
    char const *str = *(char const **)key;
    size_t hash = 5381;
    int c;
    while ((c = *str++)) {
        hash = ((hash << 5) + hash) + c;
    }
    return hash;
}

// Compare function for strings
static int string_compare(void const *a, void const *b) {
    char const *str1 = *(char const **)a;
    char const *str2 = *(char const **)b;
    return strcmp(str1, str2);
}

int main() {
    // Create a map with string keys and integer values
    dsc_unordered_map *map = unordered_map_create(sizeof(char *), sizeof(int),
                                                  string_hash, string_compare);
    if (!map) {
        printf("Failed to create map\n");
        return EXIT_FAILURE;
    }

    // Insert some key-value pairs
    char const *keys[] = {"apple", "banana", "orange", "grape", "kiwi"};
    int values[] = {1, 2, 3, 4, 5};

    for (size_t i = 0; i < 5; ++i) {
        if (unordered_map_insert(map, &keys[i], &values[i]) != DSC_ERROR_OK) {
            printf("Failed to insert %s\n", keys[i]);
            continue;
        }
        printf("Inserted %s: %d\n", keys[i], values[i]);
    }

    // Find and print values
    printf("\nFinding values:\n");
    for (size_t i = 0; i < 5; ++i) {
        int *value = (int *)unordered_map_find(map, &keys[i]);
        if (value) {
            printf("Found %s: %d\n", keys[i], *value);
        } else {
            printf("Not found: %s\n", keys[i]);
        }
    }

    // Try to find a non-existent key
    char const *non_existent = "mango";
    int *value = (int *)unordered_map_find(map, &non_existent);
    printf("\nLooking for non-existent key 'mango': %s\n",
           value ? "Found (unexpected)" : "Not found (expected)");

    // Update a value
    int new_value = 42;
    if (unordered_map_insert(map, &keys[0], &new_value) == DSC_ERROR_OK) {
        value = (int *)unordered_map_find(map, &keys[0]);
        printf("\nUpdated %s: %d\n", keys[0], *value);
    }

    // Erase a key
    if (unordered_map_erase(map, &keys[2]) == DSC_ERROR_OK) {
        printf("\nErased %s\n", keys[2]);
        value = (int *)unordered_map_find(map, &keys[2]);
        printf("Looking for erased key: %s\n",
               value ? "Found (unexpected)" : "Not found (expected)");
    }

    // Print final size
    printf("\nFinal map size: %zu\n", unordered_map_size(map));

    // Clean up
    unordered_map_destroy(map);
    return EXIT_SUCCESS;
}