/**
* 获取红黑树中结点的前驱
*/
prbt_node rbt_precursor(prbt_node current)
{
prbt_node parent = current->parent;
if (current->left != nil)
{
return rbt_maximum(current->left);
}
else if (parent != nil)
{
while(parent != nil && parent->right != current)
{
current = parent;
parent = parent->parent;
}
if(parent != nil)
{
return parent;
}
else
{
return nil;
}
}
else
{
return nil;
}
}
int main(){
Rbt_tree_link a = rbt_create();
Rbtlink it;
srand(time(NULL));
puts("Inserting...");
for(i=0;i<N;i++) {
num[i] = rand() % N;
rbt_insert(a,num[i]);
}
printf("rbt_size: %d\n",rbt_size(a));
printf("min value:%d max value:%d\n",rbt_item(rbt_minimum(a)),rbt_item(rbt_maximum(a)));
puts("Doing assert...");
rbt_assert(a);
puts("Traversing (inorder)...");
rbt_inorder(a,func);
for(i=0; i < N; i++)
rbt_search(a, i);
puts("Traversing (from max to min)...");
it = rbt_maximum(a);
for(i = rbt_size(a)-1; i >= 0; i--) {
assert(n[i] == rbt_item(it));
it = rbt_predecessor(it);
}
printf("rbt_size: %d\n",rbt_size(a));
puts("Deleting all values...");
int i = 0;
for (i = 0; i < N; ++i) {
printf("%d deleted\r", num[i]);
rbt_delete(a, num[i]);
}
puts("\nDestroying rbt..");
rbt_destroy(a);
puts("OK!");
return 0;
}
RBT_NODE *rbt_predeccessor( RBT_ROOT *root , RBT_NODE *x )
{
if ( x != &( root->nil ) ) {
if ( x->left != &( root->nil ) ) {
return rbt_maximum( root , x->left ) ;
}
else {
RBT_NODE *y = x->p ;
while ( y != &( root->nil ) && x == y->left ) {
x = y ;
y = y->p ;
}
return y ;
}
}
return NULL ;
}
