2025-12-07 18:35:22 +01:00

106 lines
2.8 KiB
C

#include "bintree.h"
#include "stack.h"
#include <string.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. */
// typedef int (*CompareFctType)(const void *arg1, const void *arg2);
// 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).
TreeNode *addToTree(TreeNode *root, const void *data, size_t dataSize,
CompareFctType compareFct, int *isDuplicate) {
if (isDuplicate) {
*isDuplicate = 0;
}
if (root == NULL) {
TreeNode *node = malloc(sizeof(TreeNode));
node->data = malloc(dataSize);
memcpy(node->data, data, dataSize);
node->left = NULL;
node->right = NULL;
return node;
}
int cmp = compareFct(data, root->data);
if (cmp < 0) {
root->left = addToTree(root->left, data, dataSize, compareFct, isDuplicate);
} else if (cmp > 0) {
root->right =
addToTree(root->right, data, dataSize, compareFct, isDuplicate);
} else {
// Duplikat
if (isDuplicate) {
*isDuplicate = 1;
}
}
return root;
}
// 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;
// Neue Iteration starten
if (root != NULL) {
clearStack(&stack);
TreeNode *curr = root;
// Alle linken Kinder pushen
while (curr != NULL) {
stack = push(stack, curr);
curr = curr->left;
}
}
// Wenn leer → fertig
if (stack == NULL)
return NULL;
// Oberstes Element lesen
TreeNode *node = (TreeNode *)stack->data;
stack = pop(stack);
// Jetzt den rechten Teilbaum verarbeiten
TreeNode *curr = node->right;
while (curr != NULL) {
stack = push(stack, curr);
curr = curr->left;
}
return node->data;
}
// 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) {
if (root == NULL)
return 0;
return 1 + treeSize(root->left) + treeSize(root->right);
}