changeset 15:d11dfc49b559

Seems to be working, but I need to prove the algorithms and also make ctrie_remove compress down, too. See the final output where the standalone 'n' node could be pushed into it's children
author Eris Caffee <discordia@eldalin.com>
date Wed, 03 Oct 2012 01:07:04 -0500
parents ef73b96fdcae
children 5d8158ad2d61
files src/ctrie.c src/ctrie.h src/ctrie_test.c
diffstat 3 files changed, 242 insertions(+), 122 deletions(-) [+]
line diff
     1.1 --- a/src/ctrie.c	Tue Oct 02 20:00:38 2012 -0500
     1.2 +++ b/src/ctrie.c	Wed Oct 03 01:07:04 2012 -0500
     1.3 @@ -61,7 +61,7 @@
     1.4     ctrie->root->data = NULL;
     1.5     ctrie->size = ctrie->count = 0;
     1.6  
     1.7 -   printf("The root node is %p\n", ctrie->root);
     1.8 +   //   printf("The root node is %p\n", (void *) ctrie->root);
     1.9     return ctrie;
    1.10     }
    1.11  
    1.12 @@ -137,8 +137,7 @@
    1.13     if ( (NULL == ctrie) || (NULL == key) )
    1.14        return NULL;
    1.15  
    1.16 -   printf("root node is ");
    1.17 -   ctrie_print_node(ctrie->root);
    1.18 +   //   printf("root node is ");  ctrie_print_node(ctrie->root);
    1.19     return ctrie_insert_node(ctrie, ctrie->root, key, data);
    1.20     }
    1.21  
    1.22 @@ -151,74 +150,81 @@
    1.23  
    1.24     struct ctrie_node * p = ctrie_longest_matching_child(node, key);
    1.25  
    1.26 -   /*
    1.27 -   printf("Longest match is ");
    1.28 +
    1.29 +   //   printf("Longest match is ");
    1.30     if (NULL != p)
    1.31        ctrie_print_node(p);
    1.32     else
    1.33        printf("(nil)\n");
    1.34 -   */
    1.35 +
    1.36  
    1.37     if (NULL == p)
    1.38        {
    1.39        // No matching child found.  Create new(key, data) as child of node
    1.40        struct ctrie_node * new = ctrie_node_new(key, data);
    1.41        if (NULL == new)
    1.42 -	 return NULL;
    1.43 +   	 return NULL;
    1.44        new->parent = node;
    1.45  
    1.46        if (NULL == node->child)
    1.47 -	 node->child = new;
    1.48 -      else 
    1.49 -	 {
    1.50 -	 struct ctrie_node * s = node->child;
    1.51 -	 while (NULL != s->next_sibling)
    1.52 -	    s = s->next_sibling;
    1.53 -	 s->next_sibling = new;
    1.54 -	 new->prev_sibling = s;
    1.55 -	 }
    1.56 +   	 node->child = new;
    1.57 +      else
    1.58 +   	 {
    1.59 +   	 struct ctrie_node * s = node->child;
    1.60 +   	 while (NULL != s->next_sibling)
    1.61 +   	    s = s->next_sibling;
    1.62 +   	 s->next_sibling = new;
    1.63 +   	 new->prev_sibling = s;
    1.64 +   	 }
    1.65        
    1.66        ctrie->size++;
    1.67        ctrie->count++;
    1.68  
    1.69 -      /*
    1.70 -      printf("Added ");
    1.71 -      ctrie_print_node(new);
    1.72 -      */
    1.73 +
    1.74 +      //      printf("Added ");  ctrie_print_node(new);
    1.75 +
    1.76  
    1.77        return key;
    1.78        }
    1.79     else if (ctrie_str_common(p->key, key) == strlen(p->key))
    1.80        {
    1.81        // Found a node whose key matches for it's entire length
    1.82 -      if (0 == strcmp(p->key, key))
    1.83 -	 {
    1.84 -	 // Key already exists.  Error
    1.85 -	 return NULL;
    1.86 -	 }
    1.87 +      // Does it match the entire rest of the key we are inserting?
    1.88 +      if (ctrie_str_common(p->key, key) == strlen(key))
    1.89 +   	 {
    1.90 +   	 if (p->data)
    1.91 +   	    {
    1.92 +   	    //	    printf("This node already exists\n");
    1.93 +   	    // Key already exists.  Error
    1.94 +   	    return NULL;
    1.95 +   	    }
    1.96 +   	 else
    1.97 +   	    {
    1.98 +   	    p->data = data;
    1.99 +   	    ctrie->count++;
   1.100 +   	    return key;
   1.101 +   	    }
   1.102 +   	 }
   1.103        else
   1.104 -	 {
   1.105 -	 // The node found has a key that is a prefix of the key we are inserting.
   1.106 -	 // Recurse with the remainder of the key
   1.107 -	 //	 printf("Recursing because node's entire key %s is a prefix of %s\n", p->key, key);
   1.108 -	 return ctrie_insert_node(ctrie, p, key+strlen(p->key), data);
   1.109 -	 }
   1.110 +   	 {
   1.111 +   	 // The node found has a key that is a prefix of the key we are inserting.
   1.112 +   	 // Recurse with the remainder of the key
   1.113 +   	 //	  printf("Recursing because node's entire key %s is a prefix of %s\n", p->key, key);
   1.114 +   	 return ctrie_insert_node(ctrie, p, key+strlen(p->key), data);
   1.115 +   	 }
   1.116        }
   1.117     else
   1.118        {
   1.119        // Found a node that matches for only part of it's length.
   1.120        // Split the node and then recurse.
   1.121  
   1.122 -      /*
   1.123 -      printf("splitting this node: ");
   1.124 -      ctrie_print_node(p);
   1.125 -      */
   1.126 +      // printf("splitting this node: ");  ctrie_print_node(p);
   1.127  
   1.128        // Get the new shorter key for p.
   1.129        int matchlen = ctrie_str_common(p->key, key);
   1.130        char * prefix = malloc(matchlen+1);
   1.131        if (NULL == prefix)
   1.132 -	 return NULL;
   1.133 +   	 return NULL;
   1.134  
   1.135        strncpy(prefix, key, matchlen);
   1.136        prefix[matchlen] = '\0';
   1.137 @@ -249,8 +255,8 @@
   1.138        */
   1.139  
   1.140        // Now add the user requested new key as a child of p
   1.141 -      //      printf("Recursing with key %s as a prefix of %s\n", p->key, key);
   1.142 -      return ctrie_insert_node(ctrie, p, key + matchlen, data);
   1.143 +      // printf("Recursing with node %p key %s as a prefix of %s\n", p->parent, p->parent->key, key);
   1.144 +      return ctrie_insert_node(ctrie, p->parent, key, data);
   1.145        }
   1.146  
   1.147     // should not get here
   1.148 @@ -265,13 +271,13 @@
   1.149     int len = 0;
   1.150     int l;
   1.151  
   1.152 -   printf("Searching for match in children of %p\n", node);
   1.153 +   //printf("Searching for >%s< in children of %p (%s)\n", key, (void *) node, node->key);
   1.154  
   1.155     struct ctrie_node * p = node->child;
   1.156     while (NULL != p)
   1.157        {
   1.158        l = ctrie_str_common(p->key, key);
   1.159 -      printf("common length is %d\n", l);
   1.160 +      //printf("     Checking >%s< common length is %d\n", p->key, l);
   1.161        if (l > len)
   1.162  	 {
   1.163  	 len = l;
   1.164 @@ -279,6 +285,8 @@
   1.165  	 }
   1.166        p = p->next_sibling;
   1.167        }
   1.168 +
   1.169 +   //printf("Returning longest match %p\n", longest);
   1.170     return longest;
   1.171     }
   1.172  
   1.173 @@ -294,10 +302,14 @@
   1.174  int
   1.175  ctrie_str_common(char * s1, char * s2)
   1.176     {
   1.177 +   //   printf("s1 >%s< s1 >%s<\n", s1, s2);
   1.178     int i = 0;
   1.179 -   while ( (*s1 != '\0') && (*s2 != '\0') &&
   1.180 +   while ( (*(s1+i) != '\0') && (*(s2+i) != '\0') &&
   1.181  	   (*(s1+i) == *(s2+i)) )
   1.182 +      {
   1.183 +      //      printf("*s1+%d %c   *s2+%d %c\n", i, (*(s1+i) == '\0' ? "." : *(s1+i)), i, (*(s2+i) == '\0' ? "." : *(s2+i)));
   1.184        i++;
   1.185 +      }
   1.186  
   1.187     return i;
   1.188     }
   1.189 @@ -309,7 +321,9 @@
   1.190     if (NULL == node)
   1.191        printf("(nil node)\n");
   1.192     else
   1.193 -      printf("%s \t%p\t parent:%p \tchild:%p \tprev:%p \tnext:%p \tdata:%p\n", node->key, node, node->parent, node->child, node->prev_sibling, node->next_sibling, node->data);
   1.194 +      printf("%s \t%p\t parent:%p \tchild:%p \tprev:%p \tnext:%p \tdata:%p\n", 
   1.195 +	     node->key, (void *) node, (void *) node->parent, (void *) node->child, 
   1.196 +	     (void *) node->prev_sibling, (void *) node->next_sibling, node->data);
   1.197  
   1.198     }
   1.199  
   1.200 @@ -376,8 +390,10 @@
   1.201  void
   1.202  ctrie_visit_node(struct ctrie * ctrie, struct ctrie_node * node, void (*op)(char * k, void * d), char * prefix)
   1.203     {
   1.204 +   //   printf("Visiting node %p with prefix >%s<\n", node, prefix);
   1.205     if (NULL != node->data)
   1.206        {
   1.207 +      //      printf("node has data\n");
   1.208        char * k = malloc(strlen(prefix) + strlen(node->key));
   1.209        if (NULL == k)
   1.210  	 return;
   1.211 @@ -390,6 +406,7 @@
   1.212  
   1.213     if(NULL != node->child)
   1.214        {
   1.215 +      //      printf("node has children\n");
   1.216        char * k = malloc(strlen(prefix) + strlen(node->key));
   1.217        if (NULL == k)
   1.218  	 return;
   1.219 @@ -426,17 +443,15 @@
   1.220     size_t len = strlen(key);
   1.221     for (int i = 0; i <= len; i += strlen(node->key))
   1.222        {
   1.223 -      node = ctrie_search_children(node, key+i);
   1.224 +      node = ctrie_longest_matching_child(node, key+i);
   1.225        if (NULL == node)
   1.226  	 return NULL;
   1.227 -      if (NULL != node->data)
   1.228 +      if (strlen(key+i) == strlen(node->key))
   1.229  	 return node;
   1.230        }
   1.231  
   1.232     // Should never get here
   1.233     return NULL;
   1.234 -
   1.235 -   struct ctrie_node * p = ctrie_longest_matching_child(node, key);
   1.236     }
   1.237  
   1.238  ////////////////////////////////////////////////////////////////////////////////
   1.239 @@ -453,73 +468,21 @@
   1.240     return p;
   1.241     }
   1.242  
   1.243 -
   1.244 -
   1.245 -
   1.246 -
   1.247 -
   1.248 -
   1.249 -
   1.250 -
   1.251 -
   1.252 -
   1.253 -
   1.254 -
   1.255 -
   1.256 -
   1.257 -
   1.258 -
   1.259 -
   1.260 -
   1.261 -
   1.262 -////////////////////////////////////////////////////////////////////////////////
   1.263 -void *
   1.264 -ctrie_remove(struct ctrie * ctrie, char * key)
   1.265 -   {
   1.266 -   if ( (NULL == ctrie) || (NULL == key) )
   1.267 -      return NULL;
   1.268 -
   1.269 -   struct ctrie_node * node = ctrie_find_node(ctrie, key);
   1.270 -   if (NULL == node)
   1.271 -      return NULL;
   1.272 -
   1.273 -   void * data = node->data;
   1.274 -
   1.275 -   while ( (NULL == node->prev_sibling) && (NULL == node->prev_sibling) ) 
   1.276 -      {
   1.277 -      struct ctrie_node * p = node;
   1.278 -      node = node->parent;
   1.279 -      free(p);
   1.280 -      ctrie->size--;
   1.281 -      }
   1.282 -
   1.283 -   if (node == ctrie->root)
   1.284 -      return data;
   1.285 -
   1.286 -   if (node->prev_sibling)
   1.287 -      node->prev_sibling->next_sibling = node->next_sibling;
   1.288 -   else
   1.289 -      node->parent->child = node->next_sibling;
   1.290 -
   1.291 -   if (node->next_sibling)
   1.292 -      node->next_sibling->prev_sibling = node->prev_sibling;
   1.293 -
   1.294 -   free(node);
   1.295 -
   1.296 -   ctrie->count--;
   1.297 -
   1.298 -   return data;
   1.299 -   }
   1.300 -
   1.301  ////////////////////////////////////////////////////////////////////////////////
   1.302  void
   1.303 -ctrie_subtree_list_push(char * k, void * d)
   1.304 +ctrie_subtree_list_push(char * key, void * data)
   1.305     {
   1.306     if (NULL == subkey_list)
   1.307        return;
   1.308 -
   1.309 +   char * k = malloc(strlen(key)+1);
   1.310 +   if (NULL == k)
   1.311 +      return;
   1.312 +   strcpy(k, key);
   1.313     if ( (0 == subkey_list_limit) || (list_size(subkey_list) < subkey_list_limit) )
   1.314 +      {
   1.315        list_push_front(subkey_list, k);
   1.316 +      //   printf("list push >%s<\n", k);
   1.317 +      }
   1.318     }
   1.319  
   1.320  ////////////////////////////////////////////////////////////////////////////////
   1.321 @@ -532,25 +495,47 @@
   1.322     if ( (NULL == ctrie) || (NULL == prefix) )
   1.323        return NULL;
   1.324  
   1.325 -   struct ctrie_node * node = ctrie_find_node(ctrie, prefix);
   1.326 +   //   struct ctrie_node * node = ctrie_find_node(ctrie, prefix);
   1.327 +
   1.328 +   struct ctrie_node * p = NULL;
   1.329 +   struct ctrie_node * node = ctrie->root;
   1.330 +   size_t len = strlen(prefix);
   1.331 +   //   printf("len %d\n", len);
   1.332 +   int index;
   1.333 +   for (int i = 0; i < len; i += ctrie_str_common(prefix+i, node->key))
   1.334 +      {
   1.335 +      //      printf("i %d\n", i);
   1.336 +      p = node;
   1.337 +      node = ctrie_longest_matching_child(node, prefix+i);
   1.338 +      //      printf("longest returned %p   %d\n", node, strlen(node->key));
   1.339 +      if (NULL == node)
   1.340 +	 {
   1.341 +	 //	 printf("breaking\n");
   1.342 +	 break;
   1.343 +	 }
   1.344 +      index = i;
   1.345 +      }
   1.346 +
   1.347     if (NULL == node)
   1.348        return NULL;
   1.349  
   1.350 +   //   printf("Found longest match as %p >%s< index is %d\n", node, node->key, index);
   1.351 +
   1.352     subkey_list = list_new();
   1.353     if (NULL == subkey_list)
   1.354        return NULL;
   1.355     subkey_list_limit = limit;
   1.356  
   1.357 -   size_t len = strlen(prefix);
   1.358 +   len = strlen(prefix);
   1.359     char * pref = malloc(len+1);
   1.360     if (NULL == pref)
   1.361        return NULL;
   1.362 -   strncpy(pref, prefix, len-1);
   1.363 -   pref[len-1] = '\0';
   1.364 -
   1.365 -   ctrie_visit_node(ctrie, node->parent, ctrie_subtree_list_push, pref);
   1.366 +   strncpy(pref, prefix, index);
   1.367 +   pref[index] = '\0';
   1.368 +   //   printf("Built pref as >%s<\n", pref);
   1.369 +   ctrie_visit_node(ctrie, node, ctrie_subtree_list_push, pref);
   1.370     free(pref);
   1.371 -
   1.372 +   //   printf("Returning\n");
   1.373     return subkey_list;
   1.374     }
   1.375  
   1.376 @@ -568,3 +553,83 @@
   1.377  
   1.378     list_delete(list);
   1.379     }
   1.380 +
   1.381 +////////////////////////////////////////////////////////////////////////////////
   1.382 +void *
   1.383 +ctrie_remove(struct ctrie * ctrie, char * key)
   1.384 +   {
   1.385 +   if ( (NULL == ctrie) || (NULL == key) )
   1.386 +      return NULL;
   1.387 +
   1.388 +   //   printf("Looking for %s\n", key);
   1.389 +   struct ctrie_node * node = ctrie_find_node(ctrie->root, key);
   1.390 +   if (NULL == node)
   1.391 +      return NULL;
   1.392 +
   1.393 +   //   printf("Found node %p ", node);  ctrie_print_node(node);
   1.394 +
   1.395 +   // We found a node, but is it an actual data node or just a prefix?
   1.396 +   if (NULL == node->data)
   1.397 +      return NULL;
   1.398 +
   1.399 +   // OK, so it's a data node.  If it has no children we can delete it.  
   1.400 +   // Otherwise we just remove the data and maybe collapse nodes
   1.401 +
   1.402 +   void * data = node->data;
   1.403 +   struct ctrie_node * parent = node->parent;
   1.404 +      
   1.405 +   if (NULL == node->child)
   1.406 +      {
   1.407 +      // Remove from sibling list.
   1.408 +      if (node->prev_sibling)
   1.409 +	 node->prev_sibling->next_sibling = node->next_sibling;
   1.410 +      if (node->next_sibling)
   1.411 +	 node->next_sibling->prev_sibling = node->prev_sibling;
   1.412 +
   1.413 +      // Point the parent to the new first child, if needed.
   1.414 +      if (parent->child == node)
   1.415 +	 {
   1.416 +	 if (node->prev_sibling)
   1.417 +	    parent->child = node->prev_sibling;
   1.418 +	 else
   1.419 +	    parent->child = node->next_sibling;
   1.420 +	 }
   1.421 +
   1.422 +      free(node->key);
   1.423 +      free(node);
   1.424 +      ctrie->size--;
   1.425 +      ctrie->count--;
   1.426 +      }
   1.427 +   else
   1.428 +      {
   1.429 +      node->data = NULL;
   1.430 +      ctrie->count--;
   1.431 +      }
   1.432 +
   1.433 +
   1.434 +   //   printf("merging nodes\n");  ctrie_dump_raw(ctrie);
   1.435 +
   1.436 +   // At this point we may have nodes that need to be collapsed together.
   1.437 +   // This happens when the parent has only one child.
   1.438 +   if (NULL == parent->child->next_sibling)
   1.439 +      {
   1.440 +      char * k = malloc(strlen(parent->key) + strlen(parent->child->key) + 1);
   1.441 +      // UGH!  I need a real error signalling mechanism to handle this.
   1.442 +      if (NULL == k)
   1.443 +	 return data;
   1.444 +      k[0] = '\0';
   1.445 +      strcat(k, parent->key);
   1.446 +      strcat(k, parent->child->key);
   1.447 +      free(parent->key);
   1.448 +      parent->key = k;
   1.449 +
   1.450 +      node = parent->child;
   1.451 +      parent->child = node->child;
   1.452 +      free(node->key);
   1.453 +      free(node);
   1.454 +      ctrie->size--;
   1.455 +      }
   1.456 +
   1.457 +   return data;
   1.458 +   }
   1.459 +
     2.1 --- a/src/ctrie.h	Tue Oct 02 20:00:38 2012 -0500
     2.2 +++ b/src/ctrie.h	Wed Oct 03 01:07:04 2012 -0500
     2.3 @@ -1,7 +1,7 @@
     2.4  #ifndef CTRIE_H_
     2.5  #define CTRIE_H_
     2.6  
     2.7 -// Compact trie - internal nodes are collapsed together if they have no siblings.
     2.8 +// Compact trie - internal nodes are collapsed together if they have no siblings.F
     2.9  
    2.10  struct ctrie;
    2.11  
     3.1 --- a/src/ctrie_test.c	Tue Oct 02 20:00:38 2012 -0500
     3.2 +++ b/src/ctrie_test.c	Wed Oct 03 01:07:04 2012 -0500
     3.3 @@ -7,7 +7,7 @@
     3.4  
     3.5  void print_val(char * key, void * data)
     3.6     {
     3.7 -   printf("%s\t\t%s\n", key, data);
     3.8 +   printf("%s\t\t%s\n", key, (char *) data);
     3.9     }
    3.10  
    3.11  int main(int argc, char ** argv)
    3.12 @@ -40,12 +40,16 @@
    3.13        i += 2;
    3.14        }
    3.15  
    3.16 -   ctrie_dump_raw(ctrie);
    3.17     ctrie_dump(ctrie);
    3.18     ctrie_walk_keys(ctrie, print_val);
    3.19 +   ctrie_dump_raw(ctrie);
    3.20     printf("ctrie is storing %zd words in %zd keys\n", ctrie_count(ctrie), ctrie_size(ctrie));
    3.21  
    3.22 -   exit(EXIT_SUCCESS);
    3.23 +   printf("\n\n\n");
    3.24 +   ctrie_insert(ctrie, "a", "indefinite article.  Used before an initial consonant sound.");
    3.25 +   ctrie_dump_raw(ctrie);
    3.26 +   printf("ctrie is storing %zd words in %zd keys\n", ctrie_count(ctrie), ctrie_size(ctrie));
    3.27 +
    3.28  
    3.29     ////////////////////////////////////////////
    3.30     printf("===================================================\n");
    3.31 @@ -69,12 +73,12 @@
    3.32        printf("Nothing found for '%s'\n", word);
    3.33     else
    3.34        {
    3.35 -      printf("list size is %d\n", list_size(list));
    3.36 +      printf("list size is %zd\n", list_size(list));
    3.37        struct list_iterator * it = list_begin(list);
    3.38        struct list_iterator * next = it;
    3.39        while (NULL != next)
    3.40  	 {
    3.41 -	 printf("%s\n", list_value(it));
    3.42 +	 printf("%s\n", (char *) list_value(it));
    3.43  	 next = list_next(it);
    3.44  	 }
    3.45        ctrie_free_subkey_list(list);
    3.46 @@ -89,23 +93,67 @@
    3.47        printf("Nothing found for '%s'\n", word);
    3.48     else
    3.49        {
    3.50 -      printf("list size is %d\n", list_size(list));
    3.51 +      printf("list size is %zd\n", list_size(list));
    3.52        struct list_iterator * it = list_begin(list);
    3.53        struct list_iterator * next = it;
    3.54        while (NULL != next)
    3.55  	 {
    3.56 -	 printf("%s\n", list_value(it));
    3.57 +	 printf("%s\n", (char *) list_value(it));
    3.58  	 next = list_next(it);
    3.59  	 }
    3.60        ctrie_free_subkey_list(list);
    3.61        }
    3.62  
    3.63 +
    3.64 +   ////////////////////////////////////////////
    3.65 +   printf("===================================================\n");
    3.66 +   strcpy(word, "he");
    3.67 +   printf("Looking for completions of '%s':\n", word);
    3.68 +   list = ctrie_get_subkeys(ctrie, word, 0);
    3.69 +   if (NULL == list)
    3.70 +      printf("Nothing found for '%s'\n", word);
    3.71 +   else
    3.72 +      {
    3.73 +      printf("list size is %zd\n", list_size(list));
    3.74 +      struct list_iterator * it = list_begin(list);
    3.75 +      struct list_iterator * next = it;
    3.76 +      while (NULL != next)
    3.77 +	 {
    3.78 +	 printf("%s\n", (char *) list_value(it));
    3.79 +	 next = list_next(it);
    3.80 +	 }
    3.81 +      ctrie_free_subkey_list(list);
    3.82 +      }
    3.83 +
    3.84 +
    3.85 +   ////////////////////////////////////////////
    3.86 +   printf("===================================================\n");
    3.87 +   strcpy(word, "helpe");
    3.88 +   printf("Looking for completions of '%s':\n", word);
    3.89 +   list = ctrie_get_subkeys(ctrie, word, 0);
    3.90 +   if (NULL == list)
    3.91 +      printf("Nothing found for '%s'\n", word);
    3.92 +   else
    3.93 +      {
    3.94 +      printf("list size is %zd\n", list_size(list));
    3.95 +      struct list_iterator * it = list_begin(list);
    3.96 +      struct list_iterator * next = it;
    3.97 +      while (NULL != next)
    3.98 +	 {
    3.99 +	 printf("%s\n", (char *) list_value(it));
   3.100 +	 next = list_next(it);
   3.101 +	 }
   3.102 +      ctrie_free_subkey_list(list);
   3.103 +      }
   3.104 +
   3.105 +
   3.106     ////////////////////////////////////////////
   3.107     printf("===================================================\n");
   3.108     strcpy(word, "anybody");
   3.109     printf("remove '%s'\n", word);
   3.110     ctrie_remove(ctrie, word);
   3.111  
   3.112 +   // remove a word that is not in the dictionary, but is a prefix of other words.  Should do nothing.
   3.113     strcpy(word, "ann");
   3.114     printf("remove '%s'\n", word);
   3.115     ctrie_remove(ctrie, word);
   3.116 @@ -118,9 +166,16 @@
   3.117     printf("remove '%s'\n", word);
   3.118     ctrie_remove(ctrie, word);
   3.119  
   3.120 -   ctrie_dump(ctrie);
   3.121 +   strcpy(word, "an");
   3.122 +   printf("remove '%s'\n", word);
   3.123 +   ctrie_remove(ctrie, word);
   3.124 +
   3.125 +   ctrie_dump_raw(ctrie);
   3.126     printf("ctrie is storing %zd words in %zd keys\n", ctrie_count(ctrie), ctrie_size(ctrie));
   3.127  
   3.128 +
   3.129 +   exit(EXIT_SUCCESS);
   3.130 +
   3.131     ////////////////////////////////////////////
   3.132     printf("===================================================\n");
   3.133     strcpy(word, "anybody");