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/* Updated: 2006-04-07 to deal with duplicate inserts */
#include <stdio.h>
#include <inttypes.h>
#include <lt_inttypes.h>
#include <stdlib.h>
#include "contain.h"
#include <assert.h>
/* a -> b */
#define implies(a,b) (!(a) || (b))
static void assert_tree(splay *tree, splay_cmp_t cmp)
{
#ifndef NDEBUG
if (!tree)
return;
assert(implies(tree->left,cmp(tree->left,tree)<0));
assert(implies(tree->right,cmp(tree,tree->right)<0));
assert(implies(tree->left && tree->right,
cmp(tree->left,tree->right)<0));
assert_tree(tree->left,cmp);
assert_tree(tree->right,cmp);
#endif
}
#undef implies
splay *splay_search_tree(splay *tree, splay_cmp_t cmp, splay *node) {
if (tree == NULL) {
return NULL;
}
assert_tree(tree,cmp);
for (;;) {
int cmpres = cmp(node,tree);
if (cmpres<0) {
splay *y;
if (tree->left == NULL)
break;
/* Rotate Right */
y = tree->left;
tree->left=y->right;
y->right=tree;
tree=y;
/* Not found? */
if (cmp(node,tree)>0) {
break;
}
} else if (cmpres>0) {
splay *y;
if (tree->right == NULL)
break;
/* Rotate Left */
y = tree->right;
tree->right=y->left;
y->left=tree;
tree=y;
/* Not found? */
if (cmp(node,tree)<0) {
break;
}
} else {
/* Found it */
break;
}
}
assert_tree(tree,cmp);
return tree;
}
splay *splay_delete(splay *tree, splay_cmp_t cmp, splay *node) {
splay *s;
if (!tree)
return 0;
tree = splay_search_tree(tree, cmp, node);
if (cmp(tree,node)==0) {
if (tree->left == NULL) {
s = tree->right;
} else {
s = splay_search_tree(tree->left, cmp, node);
s->right = tree->right;
}
free(tree);
return s;
}
return tree;
}
void splay_purge(splay *tree) {
if (!tree)
return;
if (tree->left)
splay_purge(tree->left);
if (tree->right)
splay_purge(tree->right);
free(tree);
}
splay *splay_insert(splay *tree, splay_cmp_t cmp, splay *node)
{
int cmpres;
assert_tree(tree,cmp);
if (tree == NULL) {
tree = node;
node->left = NULL;
node->right = NULL;
assert_tree(tree,cmp);
return tree;
}
assert_tree(tree,cmp);
cmpres=cmp(node,tree);
if (cmpres<0) {
tree=splay_insert(tree->left,cmp,node);
} else if (cmpres>0) {
tree=splay_insert(tree->right,cmp,node);
} else {
/* Replace the root node with the current node */
node->left = tree->left;
node->right = tree->right;
free(tree);
tree=node;
}
assert_tree(tree,cmp);
return tree;
}
void splay_visit(const splay *tree, visitor_t pre,visitor_t inorder,visitor_t post,void *userdata)
{
if (!tree) return;
if (pre) pre(tree,userdata);
splay_visit(tree->left,pre,inorder,post,userdata);
if (inorder) inorder(tree,userdata);
splay_visit(tree->right,pre,inorder,post,userdata);
if (post) post(tree,userdata);
}
#ifdef TEST
#include <string.h>
struct foo_t {
splay tree;
char *key;
char *value;
};
void visitor_inorder(const struct foo_t *a)
{
printf("%s: %s\n",a->key,a->value);
}
int cmp(const struct foo_t *a,const struct foo_t *b)
{
int ret= strcmp(a->key,b->key);
printf("cmp(%s,%s)==%i\n",a->key,b->key,ret);
return ret;
}
int main(int argc, char *argv[])
{
struct foo_t *tree = NULL;
struct foo_t a = { { NULL, NULL }, "a","apple" };
struct foo_t b = { { NULL, NULL }, "b","bear" };
struct foo_t q = { { NULL, NULL }, "a", NULL };
struct foo_t *node;
tree=(struct foo_t *)splay_insert((splay*)tree,(splay_cmp_t)cmp,(splay*)&a);
splay_dump((splay*)tree,visitor_pre,visitor_inorder,visitor_post);
tree=(struct foo_t *)splay_insert((splay*)tree,(splay_cmp_t)cmp,(splay*)&b);
splay_dump((splay*)tree,visitor_pre,visitor_inorder,visitor_post);
tree=(struct foo_t*)splay_search_tree((splay*)tree,(splay_cmp_t)cmp,(splay *)&q);
printf("%s is for %s\n",q.key,tree->value);
splay_dump((splay*)tree,visitor_pre,visitor_inorder,visitor_post);
tree=(struct foo_t*)splay_search_tree((splay*)tree,(splay_cmp_t)cmp,(splay *)&q);
printf("%s is for %s\n",q.key,tree->value);
splay_dump((splay*)tree,visitor_pre,visitor_inorder,visitor_post);
q.key="b";
tree=(struct foo_t*)splay_search_tree((splay*)tree,(splay_cmp_t)cmp,(splay *)&q);
printf("%s is for %s\n",q.key,tree->value);
splay_dump((splay*)tree,visitor_pre,visitor_inorder,visitor_post);
tree=(struct foo_t*)splay_search_tree((splay*)tree,(splay_cmp_t)cmp,(splay *)&q);
printf("%s is for %s\n",q.key,tree->value);
splay_dump((splay*)tree,visitor_pre,visitor_inorder,visitor_post);
return 0;
}
#endif
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