trie.h

常用的数据结构和算法函数库

/*

Copyright (c) 2005, Simon Howard
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/**
 * @file trie.h
 *
 * @brief Fast string lookups
 *
 * A trie is a data structure which provides fast mappings from strings
 * to values.
 *
 * To create a new trie, use @ref trie_new.  To destroy a trie,
 * use @ref trie_free.
 *
 * To insert a value into a trie, use @ref trie_insert. To remove a value
 * from a trie, use @ref trie_remove.  
 *
 * To look up a value from its key, use @ref trie_lookup.
 *
 * To find the number of entries in a trie, use @ref trie_num_entries.
 */

#ifndef ALGORITHM_TRIE_H
#define ALGORITHM_TRIE_H

#ifdef __cplusplus
extern "C" {
#endif

typedef struct _Trie Trie;

/**
 * Create a new trie.
 *
 * @return                   Pointer to a new trie structure.
 */

Trie *trie_new(void);

/** 
 * Destroy a trie.
 *
 * @param trie               The trie to destroy.
 */

void trie_free(Trie *trie);

/**
 * Insert a new key-value pair into a trie.
 *
 * @param trie               The trie.
 * @param key                The key to access the new value.
 * @param value              The value.
 */

void trie_insert(Trie *trie, char *key, void *value);

/**
 * Look up a value from its key in a trie.
 *
 * @param trie               The trie.
 * @param key                The key.
 * @return                   The value associated with the key, or NULL if
 *                           not found in the trie.
 */

void *trie_lookup(Trie *trie, char *key);

/**
 * Remove an entry from a trie.
 *
 * @param trie               The trie.
 * @param key                The key of the entry to remove.
 */

void trie_remove(Trie *trie, char *key);

/** 
 * Find the number of entries in a trie.
 *
 * @param trie               The trie.
 * @return                   Count of the number of entries in the trie.
 */

int trie_num_entries(Trie *trie);

#ifdef __cplusplus
}
#endif

#endif /* #ifndef ALGORITHM_TRIE_H */