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Optimize arrToTree function

Browse Source 
in java, cpp, py, go, js, ts.
This commit is contained in:
Yudong Jin
2023-01-08 19:03:22 +08:00
parent c411969bd1
commit dcc3b2e35b
29 changed files with 222 additions and 114 deletions
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3
codes/cpp/chapter_tree/binary_tree_bfs.cpp
View File

@@ -30,8 +30,7 @@ vector<int> hierOrder(TreeNode* root) {
int main() {
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
TreeNode* root = vecToTree(vector<int>
{ 1, 2, 3, 4, 5, 6, 7, INT_MAX, INT_MAX, INT_MAX, INT_MAX, INT_MAX, INT_MAX, INT_MAX, INT_MAX });
TreeNode* root = vecToTree(vector<int> { 1, 2, 3, 4, 5, 6, 7 });
cout << endl << "初始化二叉树\n" << endl;
PrintUtil::printTree(root);

3
codes/cpp/chapter_tree/binary_tree_dfs.cpp
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@@ -41,8 +41,7 @@ void postOrder(TreeNode* root) {
int main() {
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
TreeNode* root = vecToTree(vector<int>
{ 1, 2, 3, 4, 5, 6, 7, INT_MAX, INT_MAX, INT_MAX, INT_MAX, INT_MAX, INT_MAX, INT_MAX, INT_MAX});
TreeNode* root = vecToTree(vector<int> { 1, 2, 3, 4, 5, 6, 7 });
cout << endl << "初始化二叉树\n" << endl;
PrintUtil::printTree(root);

15
codes/cpp/include/TreeNode.hpp
View File

@@ -27,23 +27,24 @@ struct TreeNode {
* @return TreeNode*
*/
TreeNode *vecToTree(vector<int> list) {
if (list.empty()) {
if (list.empty())
return nullptr;
}
auto *root = new TreeNode(list[0]);
queue<TreeNode *> que;
size_t n = list.size(), index = 1;
while (index < n) {
que.emplace(root);
size_t n = list.size(), index = 0;
while (!que.empty()) {
auto node = que.front();
que.pop();
if (++index >= n) break;
if (index < n) {
node->left = new TreeNode(list[index++]);
node->left = new TreeNode(list[index]);
que.emplace(node->left);
}
if (++index >= n) break;
if (index < n) {
node->right = new TreeNode(list[index++]);
node->right = new TreeNode(list[index]);
que.emplace(node->right);
}
}

3
codes/csharp/chapter_tree/binary_tree_bfs.cs
View File

@@ -41,8 +41,7 @@ namespace hello_algo.chapter_tree
{
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
TreeNode? root = TreeNode.ArrToTree(new int?[] {
1, 2, 3, 4, 5, 6, 7, null, null, null, null, null, null, null, null});
TreeNode? root = TreeNode.ArrToTree(new int?[] { 1, 2, 3, 4, 5, 6, 7 });
Console.WriteLine("\n初始化二叉树\n");
PrintUtil.PrintTree(root);

3
codes/csharp/chapter_tree/binary_tree_dfs.cs
View File

@@ -57,8 +57,7 @@ namespace hello_algo.chapter_tree
{
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
TreeNode? root = TreeNode.ArrToTree(new int?[] {
1, 2, 3, 4, 5, 6, 7, null, null, null, null, null, null, null, null});
TreeNode? root = TreeNode.ArrToTree(new int?[] { 1, 2, 3, 4, 5, 6, 7 });
Console.WriteLine("\n初始化二叉树\n");
PrintUtil.PrintTree(root);

10
codes/csharp/include/TreeNode.cs
View File

@@ -19,7 +19,7 @@ namespace hello_algo.include
}
/**
* Generate a binary tree with an array
* Generate a binary tree given an array
* @param arr
* @return
*/
@@ -31,22 +31,22 @@ namespace hello_algo.include
TreeNode root = new TreeNode((int) arr[0]);
Queue<TreeNode> queue = new Queue<TreeNode>();
queue.Enqueue(root);
int i = 1;
while (queue.Count!=0)
int i = 0;
while (queue.Count != 0)
{
TreeNode node = queue.Dequeue();
if (++i >= arr.Length) break;
if (arr[i] != null)
{
node.left = new TreeNode((int) arr[i]);
queue.Enqueue(node.left);
}
i++;
if (++i >= arr.Length) break;
if (arr[i] != null)
{
node.right = new TreeNode((int) arr[i]);
queue.Enqueue(node.right);
}
i++;
}
return root;
}

6
codes/go/chapter_tree/binary_tree_bfs_test.go
View File

@@ -14,11 +14,11 @@ import (
func TestLevelOrder(t *testing.T) {
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
root := ArrayToTree([]int{1, 2, 3, 4, 5, 6, 7})
fmt.Println("初始化二叉树: ")
root := ArrToTree([]int{1, 2, 3, 4, 5, 6, 7})
fmt.Println("\n初始化二叉树: ")
PrintTree(root)
// 层序遍历
nums := levelOrder(root)
fmt.Println("层序遍历的结点打印序列 =", nums)
fmt.Println("\n层序遍历的结点打印序列 =", nums)
}

10
codes/go/chapter_tree/binary_tree_dfs_test.go
View File

@@ -14,22 +14,22 @@ import (
func TestPreInPostOrderTraversal(t *testing.T) {
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
root := ArrayToTree([]int{1, 2, 3, 4, 5, 6, 7})
fmt.Println("初始化二叉树: ")
root := ArrToTree([]int{1, 2, 3, 4, 5, 6, 7})
fmt.Println("\n初始化二叉树: ")
PrintTree(root)
// 前序遍历
nums = nil
preOrder(root)
fmt.Println("前序遍历的结点打印序列 =", nums)
fmt.Println("\n前序遍历的结点打印序列 =", nums)
// 中序遍历
nums = nil
inOrder(root)
fmt.Println("中序遍历的结点打印序列 =", nums)
fmt.Println("\n中序遍历的结点打印序列 =", nums)
// 后序遍历
nums = nil
postOrder(root)
fmt.Println("后序遍历的结点打印序列 =", nums)
fmt.Println("\n后序遍历的结点打印序列 =", nums)
}

10
codes/go/pkg/tree_node.go
View File

@@ -22,8 +22,8 @@ func NewTreeNode(v int) *TreeNode {
}
}
// ArrayToTree Generate a binary tree with an array
func ArrayToTree(arr []int) *TreeNode {
// ArrToTree Generate a binary tree given an array
func ArrToTree(arr []int) *TreeNode {
if len(arr) <= 0 {
return nil
}
@@ -31,19 +31,19 @@ func ArrayToTree(arr []int) *TreeNode {
// Let container.list as queue
queue := list.New()
queue.PushBack(root)
i := 1
i := 0
for queue.Len() > 0 {
// poll
node := queue.Remove(queue.Front()).(*TreeNode)
i++
if i < len(arr) {
node.Left = NewTreeNode(arr[i])
queue.PushBack(node.Left)
i++
}
i++
if i < len(arr) {
node.Right = NewTreeNode(arr[i])
queue.PushBack(node.Right)
i++
}
}
return root

2
codes/go/pkg/tree_node_test.go
View File

@@ -11,7 +11,7 @@ import (
func TestTreeNode(t *testing.T) {
arr := []int{2, 3, 5, 6, 7}
node := ArrayToTree(arr)
node := ArrToTree(arr)
// print tree
PrintTree(node)

115
codes/java/chapter_heap/my_heap.java Normal file
View File

@@ -0,0 +1,115 @@
/**
* File: my_heap.java
* Created Time: 2023-01-07
* Author: Krahets (krahets@163.com)
*/
package chapter_heap;
import include.*;
import java.util.*;
class MaxHeap {
private List<Integer> heap;
public MaxHeap() {
heap = new ArrayList<>();
}
public MaxHeap(List<Integer> nums) {
// 将元素拷贝至堆中
heap = new ArrayList<>(nums);
// 堆化除叶结点外的其他所有结点
for (int i = parent(size() - 1); i >= 0; i--) {
heapify(i);
}
}
/* 获取左子结点 */
private int left(int i) {
return 2 * i + 1;
}
/* 获取右子结点 */
private int right(int i) {
return 2 * i + 2;
}
/* 获取父结点 */
private int parent(int i) {
return (i - 1) / 2;
}
/* 交换元素 */
private void swap(int i, int j) {
int tmp = heap.get(i);
heap.set(i, j);
heap.set(j, tmp);
}
public int size() {
return heap.size();
}
public boolean isEmpty() {
return size() == 0;
}
/* 获取堆顶元素 */
public int peek() {
return heap.get(0);
}
/* 元素入堆 */
public void push(int val) {
heap.add(val);
// 从底至顶堆化
int i = size();
while (true) {
int p = parent(i);
if (p < 0 || heap.get(i) > heap.get(p))
break;
swap(i, p);
i = p;
}
}
/* 元素出堆 */
public int poll() {
// 判空处理
if (isEmpty())
throw new EmptyStackException();
// 交换根结点与右下角（即最后一个）结点
swap(0, size() - 1);
// 删除结点
int val = heap.remove(size() - 1);
// 从顶至底堆化
heapify(0);
// 返回堆顶元素
return val;
}
/* 从结点 i 开始，从顶至底堆化 */
private void heapify(int i) {
while (true) {
// 判断结点 i, l, r 中的最大结点，记为 ma ；
int l = left(i), r = right(i), ma = i;
if (heap.get(l) > heap.get(ma)) ma = l;
if (heap.get(r) > heap.get(ma)) ma = r;
// 若结点 i 最大，则无需继续堆化，跳出
if (ma == i) break;
// 交换结点 i 与结点 max
swap(i, ma);
// 循环向下堆化
i = ma;
}
}
}
public class my_heap {
public static void main(String[] args) {
}
}

3
codes/java/chapter_tree/binary_tree_bfs.java
View File

@@ -30,8 +30,7 @@ public class binary_tree_bfs {
public static void main(String[] args) {
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
TreeNode root = TreeNode.arrToTree(new Integer[] {
1, 2, 3, 4, 5, 6, 7, null, null, null, null, null, null, null, null });
TreeNode root = TreeNode.arrToTree(new Integer[] { 1, 2, 3, 4, 5, 6, 7 });
System.out.println("\n初始化二叉树\n");
PrintUtil.printTree(root);

3
codes/java/chapter_tree/binary_tree_dfs.java
View File

@@ -43,8 +43,7 @@ public class binary_tree_dfs {
public static void main(String[] args) {
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
TreeNode root = TreeNode.arrToTree(new Integer[] {
1, 2, 3, 4, 5, 6, 7, null, null, null, null, null, null, null, null});
TreeNode root = TreeNode.arrToTree(new Integer[] { 1, null, 3, 4, 5 });
System.out.println("\n初始化二叉树\n");
PrintUtil.printTree(root);

8
codes/java/include/PrintUtil.java
View File

@@ -8,6 +8,7 @@ package include;
import java.util.*;
class Trunk {
Trunk prev;
String str;
@@ -103,4 +104,11 @@ public class PrintUtil {
System.out.println(kv.getKey() + " -> " + kv.getValue());
}
}
public static void printHeap(PriorityQueue<Integer> queue) {
Integer[] nums = (Integer[])queue.toArray();
TreeNode root = TreeNode.arrToTree(nums);
printTree(root);
}
}

24
codes/java/include/TreeNode.java
View File

@@ -22,7 +22,7 @@ public class TreeNode {
}
/**
* Generate a binary tree with an array
* Generate a binary tree given an array
* @param arr
* @return
*/
@@ -32,19 +32,19 @@ public class TreeNode {
TreeNode root = new TreeNode(arr[0]);
Queue<TreeNode> queue = new LinkedList<>() {{ add(root); }};
int i = 1;
int i = 0;
while(!queue.isEmpty()) {
TreeNode node = queue.poll();
if (++i >= arr.length) break;
if(arr[i] != null) {
node.left = new TreeNode(arr[i]);
queue.add(node.left);
}
i++;
if (++i >= arr.length) break;
if(arr[i] != null) {
node.right = new TreeNode(arr[i]);
queue.add(node.right);
}
i++;
}
return root;
}
@@ -71,20 +71,4 @@ public class TreeNode {
}
return list;
}
/**
* Get a tree node with specific value in a binary tree
* @param root
* @param val
* @return
*/
public static TreeNode getTreeNode(TreeNode root, int val) {
if (root == null)
return null;
if (root.val == val)
return root;
TreeNode left = getTreeNode(root.left, val);
TreeNode right = getTreeNode(root.right, val);
return left != null ? left : right;
}
}

4
codes/javascript/chapter_tree/binary_tree_bfs.js
View File

@@ -28,10 +28,10 @@ function hierOrder(root) {
/* Driver Code */
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
var root = arrToTree([1, 2, 3, 4, 5, 6, 7, null, null, null, null, null, null, null, null]);
var root = arrToTree([1, 2, 3, 4, 5, 6, 7]);
console.log("\n初始化二叉树\n");
printTree(root);
/* 层序遍历 */
let list = hierOrder(root);
console.log("\n层序遍历的结点打印序列 = " + list);
console.log("\n层序遍历的结点打印序列 = " + list);

3
codes/javascript/chapter_tree/binary_tree_dfs.js
View File

@@ -40,7 +40,7 @@ function postOrder(root) {
/* Driver Code */
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
var root = arrToTree([1, 2, 3, 4, 5, 6, 7, null, null, null, null, null, null, null, null]);
var root = arrToTree([1, 2, 3, 4, 5, 6, 7]);
console.log("\n初始化二叉树\n");
printTree(root);
@@ -58,4 +58,3 @@ console.log("\n中序遍历的结点打印序列 = " + list);
list.length = 0;
postOrder(root);
console.log("\n后序遍历的结点打印序列 = " + list);

15
codes/javascript/include/TreeNode.js
View File

@@ -14,7 +14,7 @@ function TreeNode(val, left, right) {
}
/**
* Generate a binary tree with an array
* Generate a binary tree given an array
* @param arr
* @return
*/
@@ -24,20 +24,21 @@ function arrToTree(arr) {
let root = new TreeNode(arr[0]);
let queue = [root]
let i = 1;
while(queue.length) {
let i = 0;
while (queue.length) {
let node = queue.shift();
if(arr[i] !== null) {
if (++i >= arr.length) break;
if (arr[i] !== null) {
node.left = new TreeNode(arr[i]);
queue.push(node.left);
}
i++;
if(arr[i] !== null) {
if (++i >= arr.length) break;
if (arr[i] !== null) {
node.right = new TreeNode(arr[i]);
queue.push(node.right);
}
i++;
}
return root;
}

2
codes/python/chapter_tree/binary_search_tree.py
View File

@@ -138,7 +138,7 @@ class BinarySearchTree:
""" Driver Code """
if __name__ == "__main__":
# 初始化二叉搜索树
nums = list(range(1, 16))
nums = list(range(1, 16)) # [1, 2, ..., 15]
bst = BinarySearchTree(nums=nums)
print("\n初始化的二叉树为\n")
print_tree(bst.root)

2
codes/python/chapter_tree/binary_tree.py
View File

@@ -36,5 +36,5 @@ if __name__ == "__main__":
print_tree(n1)
# 删除结点
n1.left = n2
print("\n删除结点 P 后\n");
print("\n删除结点 P 后\n")
print_tree(n1)

2
codes/python/chapter_tree/binary_tree_bfs.py
View File

@@ -32,7 +32,7 @@ def hier_order(root: TreeNode):
if __name__ == "__main__":
# 初始化二叉树
# 这里借助了一个从数组直接生成二叉树的函数
root = list_to_tree(arr=[1, 2, 3, 4, 5, 6, 7, None, None, None, None, None, None, None, None])
root = list_to_tree(arr=[1, 2, 3, 4, 5, 6, 7])
print("\n初始化二叉树\n")
print_tree(root)

2
codes/python/chapter_tree/binary_tree_dfs.py
View File

@@ -45,7 +45,7 @@ def post_order(root: typing.Optional[TreeNode]):
if __name__ == "__main__":
# 初始化二叉树
# 这里借助了一个从数组直接生成二叉树的函数
root = list_to_tree(arr=[1, 2, 3, 4, 5, 6, 7, None, None, None, None, None, None, None, None])
root = list_to_tree(arr=[1, 2, 3, 4, 5, 6, 7])
print("\n初始化二叉树\n")
print_tree(root)

36
codes/python/include/binary_tree.py
View File

@@ -26,39 +26,30 @@ class TreeNode:
def list_to_tree(arr):
"""Generate a binary tree with a list
Args:
arr ([type]): [description]
Returns:
[type]: [description]
"""
if not arr:
return None
i = 1
root = TreeNode(int(arr[0]))
queue = collections.deque()
queue.append(root)
i = 0
root = TreeNode(arr[0])
queue = collections.deque([root])
while queue:
node = queue.popleft()
i += 1
if i >= len(arr): break
if arr[i] != None:
node.left = TreeNode(int(arr[i]))
node.left = TreeNode(arr[i])
queue.append(node.left)
i += 1
if i >= len(arr): break
if arr[i] != None:
node.right = TreeNode(int(arr[i]))
node.right = TreeNode(arr[i])
queue.append(node.right)
i += 1
return root
def tree_to_list(root):
"""Serialize a tree into an array
Args:
root ([type]): [description]
Returns:
[type]: [description]
"""
if not root: return []
queue = collections.deque()
@@ -75,13 +66,6 @@ def tree_to_list(root):
def get_tree_node(root, val):
"""Get a tree node with specific value in a binary tree
Args:
root ([type]): [description]
val ([type]): [description]
Returns:
[type]: [description]
"""
if not root:
return

2
codes/typescript/chapter_tree/binary_tree_bfs.ts
View File

@@ -30,7 +30,7 @@ function hierOrder(root: TreeNode | null): number[] {
/* Driver Code */
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
var root = arrToTree([1, 2, 3, 4, 5, 6, 7, null, null, null, null, null, null, null, null]);
var root = arrToTree([1, 2, 3, 4, 5, 6, 7]);
console.log('\n初始化二叉树\n');
printTree(root);

2
codes/typescript/chapter_tree/binary_tree_dfs.ts
View File

@@ -47,7 +47,7 @@ function postOrder(root: TreeNode | null): void {
/* Driver Code */
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
const root = arrToTree([1, 2, 3, 4, 5, 6, 7, null, null, null, null, null, null, null, null]);
const root = arrToTree([1, 2, 3, 4, 5, 6, 7]);
console.log('\n初始化二叉树\n');
printTree(root);

8
codes/typescript/module/TreeNode.ts
View File

@@ -20,7 +20,7 @@ class TreeNode {
}
/**
* Generate a binary tree with an array
* Generate a binary tree given an array
* @param arr
* @return
*/
@@ -31,19 +31,19 @@ function arrToTree(arr: (number | null)[]): TreeNode | null {
const root = new TreeNode(arr[0] as number);
const queue = [root];
let i = 1;
let i = 0;
while (queue.length) {
let node = queue.shift() as TreeNode;
if (++i >= arr.length) break;
if (arr[i] !== null) {
node.left = new TreeNode(arr[i] as number);
queue.push(node.left);
}
i++;
if (++i >= arr.length) break;
if (arr[i] !== null) {
node.right = new TreeNode(arr[i] as number);
queue.push(node.right);
}
i++;
}
return root;
}