2025-12-14 20:52:14 +01:00

134 lines
3.4 KiB
C

#include <string.h>
#include "stack.h"
#include "bintree.h"
// TODO: binären Suchbaum implementieren
/* * `addToTree`: fügt ein neues Element in den Baum ein (rekursiv),
* `clearTree`: gibt den gesamten Baum frei (rekursiv),
* `treeSize`: zählt die Knoten im Baum (rekursiv),
* `nextTreeData`: Traversierung mit Hilfe des zuvor implementierten Stacks. */
static TreeNode *createNode(const void *data, size_t dataSize)
{
TreeNode *newNode = calloc(1, sizeof(TreeNode));
if (!newNode)
return NULL;
newNode->data = malloc(dataSize);
if (!newNode->data)
{
free(newNode);
return 0;
}
newNode->data = data;
return newNode;
}
// Adds a copy of data's pointer destination to the tree using compareFct for ordering. Accepts duplicates
// if isDuplicate is NULL, otherwise ignores duplicates and sets isDuplicate to 1 (or to 0 if a new entry is added).
// 1. Fall: isDuplicate = NULL -> accepts
// 2. Fall: other -> ignores duplicates and
TreeNode *addToTree(TreeNode *root, const void *data, size_t dataSize, CompareFctType compareFct, int *isDuplicate)
{
if (isDuplicate != NULL)
{
*isDuplicate = 0;
}
if (!root)
{ // wurzerl == 0;
TreeNode *newNode = createNode(data, dataSize);
return newNode;
}
// wenn duplicate NUll -> doppelt hinzufügen
//
if (compareFct(data, root->data) < 0)
{
root->left = addToTree(root->left, data, dataSize, compareFct, isDuplicate);
}
else if (compareFct(data, root->data) > 0)
{
root->right = addToTree(root->right, data, dataSize, compareFct, isDuplicate);
}
else if (compareFct(data, root->data) == 0)
{
if (isDuplicate != NULL)
{
*isDuplicate = 1;
}
else
{
root->right = addToTree(root->right, data, dataSize, compareFct, isDuplicate);
}
}
}
// Iterates over the tree given by root. Follows the usage of strtok. If tree is NULL,
// the next entry of the last tree given is returned in ordering direction.
// Use your implementation of a stack to organize the iterator. Push the root node and
// all left nodes first. On returning the next element,
// push the top node and push all its left nodes.
void *nextTreeData(TreeNode *root)
{
static StackNode *stack = NULL;
if (root != NULL)
{
clearStack(stack);
stack = push(NULL, root);
while (root->left != NULL)
{
root = root->left;
stack = push(stack, root);
}
}
if (stack == NULL)
{
return NULL;
}
TreeNode *result = (TreeNode *)top(stack);
stack = pop(stack);
root = result;
if (root->right != NULL)
{
root = root->right;
stack = push(stack, root);
while (root->left != NULL)
{
root = root->left;
stack = push(stack, root);
}
}
return result;
}
// Releases all memory resources (including data copies).
void clearTree(TreeNode *root)
{
if (root == NULL)
{
return;
}
clearTree(root->left);
clearTree(root->right);
free(root->data);
free(root);
}
// Returns the number of entries in the tree given by root.
unsigned int treeSize(const TreeNode* root)
{
unsigned int treeSize = 0;
TreeNode* data = nextTreeData(root);
while (data != NULL)
{
treeSize++;
data = nextTreeData(NULL);
}
return treeSize;
}