mirror of
https://github.com/krahets/hello-algo.git
synced 2025-11-01 03:24:24 +08:00
108 lines
2.5 KiB
C
108 lines
2.5 KiB
C
/**
|
|
* File: tree_node.h
|
|
* Created Time: 2023-01-09
|
|
* Author: Reanon (793584285@qq.com)
|
|
*/
|
|
|
|
#ifndef TREE_NODE_H
|
|
#define TREE_NODE_H
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
#include <limits.h>
|
|
|
|
#define MAX_NODE_SIZE 5000
|
|
|
|
/* 二叉树节点结构体 */
|
|
typedef struct TreeNode {
|
|
int val; // 节点值
|
|
int height; // 节点高度
|
|
struct TreeNode *left; // 左子节点指针
|
|
struct TreeNode *right; // 右子节点指针
|
|
} TreeNode;
|
|
|
|
/* 构造函数 */
|
|
TreeNode *newTreeNode(int val) {
|
|
TreeNode *node;
|
|
|
|
node = (TreeNode *)malloc(sizeof(TreeNode));
|
|
node->val = val;
|
|
node->height = 0;
|
|
node->left = NULL;
|
|
node->right = NULL;
|
|
return node;
|
|
}
|
|
|
|
// 序列化编码规则请参考：
|
|
// https://www.hello-algo.com/chapter_tree/array_representation_of_tree/
|
|
// 二叉树的数组表示：
|
|
// [1, 2, 3, 4, None, 6, 7, 8, 9, None, None, 12, None, None, 15]
|
|
// 二叉树的链表表示：
|
|
// /——— 15
|
|
// /——— 7
|
|
// /——— 3
|
|
// | \——— 6
|
|
// | \——— 12
|
|
// ——— 1
|
|
// \——— 2
|
|
// | /——— 9
|
|
// \——— 4
|
|
// \——— 8
|
|
|
|
/* 将列表反序列化为二叉树：递归 */
|
|
TreeNode *arrayToTreeDFS(int *arr, int size, int i) {
|
|
if (i < 0 || i >= size || arr[i] == INT_MAX) {
|
|
return NULL;
|
|
}
|
|
TreeNode *root = (TreeNode *)malloc(sizeof(TreeNode));
|
|
root->val = arr[i];
|
|
root->left = arrayToTreeDFS(arr, size, 2 * i + 1);
|
|
root->right = arrayToTreeDFS(arr, size, 2 * i + 2);
|
|
return root;
|
|
}
|
|
|
|
/* 将列表反序列化为二叉树 */
|
|
TreeNode *arrayToTree(int *arr, int size) {
|
|
return arrayToTreeDFS(arr, size, 0);
|
|
}
|
|
|
|
/* 将二叉树序列化为列表：递归 */
|
|
void treeToArrayDFS(TreeNode *root, int i, int *res, int *size) {
|
|
if (root == NULL) {
|
|
return;
|
|
}
|
|
while (i >= *size) {
|
|
res = realloc(res, (*size + 1) * sizeof(int));
|
|
res[*size] = INT_MAX;
|
|
(*size)++;
|
|
}
|
|
res[i] = root->val;
|
|
treeToArrayDFS(root->left, 2 * i + 1, res, size);
|
|
treeToArrayDFS(root->right, 2 * i + 2, res, size);
|
|
}
|
|
|
|
/* 将二叉树序列化为列表 */
|
|
int *treeToArray(TreeNode *root, int *size) {
|
|
*size = 0;
|
|
int *res = NULL;
|
|
treeToArrayDFS(root, 0, res, size);
|
|
return res;
|
|
}
|
|
|
|
/* 释放二叉树内存 */
|
|
void freeMemoryTree(TreeNode *root) {
|
|
if (root == NULL)
|
|
return;
|
|
freeMemoryTree(root->left);
|
|
freeMemoryTree(root->right);
|
|
free(root);
|
|
}
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif // TREE_NODE_H
|