trie_children (Set)

Gets the values in a trie that start with the specified value.

Syntax

unsigned int trie_children(TrieSet* trie, value_type* value, value_type** out_values, unsigned int size, unsigned int max_length, bool allocate_results);

Returns: If out_values is not NULL, the number of items added to out_values. Otherwise, this returns the number of items that start with value and are no longer than max_length.

Remarks

If value is NULL, gets all of the children. Consider using the trie_iter extension.

If out_values is NULL, returns the result of trie_children_count.

If allocate_results is true, the items in out_values will be allocated by this function. In this case, it’s up to the caller to free the memory. Otherwise, it’s expected that each item in out_values should be big enough to fit an item as large as max_length + 1 (to null-terminate).

When the function allocates the results, it uses the minimum amount of space necessary for each value, so it is more memory efficient, but if the memory is already allocated, might as well use the existing space.

Example

TRIE_SET_DEFINE_H(StringTrie, str_trie, char)
TRIE_SET_DEFINE_C(StringTrie, str_trie, char)

StringTrie* trie = str_trie_create();

str_trie_add(trie, "adam");
str_trie_add(trie, "alex");
str_trie_add(trie, "alejandro");

unsigned int size = 4;
char** values = malloc(4 * sizeof(*values));

unsigned int count = str_trie_children(trie, "al", values, size, INT_MAX, true);

printf("Count: %u\n", count);

for(int i = 0; i < count; i++) {
    printf("%s\n", values[i]);
}

// Make sure to clean up the memory allocated by the function.
for(int i = 0; i < count; i++) {
    free(values[i]);
}

str_trie_free(trie);

// Output:
// Count: 2
// alex
// alejandro