From a2b7586c986733f81c6549b9bff7c3fbb98dd267 Mon Sep 17 00:00:00 2001 From: pengchzn Date: Wed, 30 Nov 2022 12:15:50 +0800 Subject: [PATCH 1/7] Add python code for queue --- .../chapter_stack_and_queue/array_queue.py | 91 ++++++++++++++++++- codes/python/chapter_stack_and_queue/deque.py | 43 ++++++++- .../linkedlist_queue.py | 88 +++++++++++++++++- codes/python/chapter_stack_and_queue/queue.py | 38 +++++++- 4 files changed, 248 insertions(+), 12 deletions(-) diff --git a/codes/python/chapter_stack_and_queue/array_queue.py b/codes/python/chapter_stack_and_queue/array_queue.py index 7bc6a32..0e173fe 100644 --- a/codes/python/chapter_stack_and_queue/array_queue.py +++ b/codes/python/chapter_stack_and_queue/array_queue.py @@ -1,10 +1,95 @@ ''' File: array_queue.py -Created Time: 2022-11-25 -Author: Krahets (krahets@163.com) +Created Time: 2022-11-29 +Author: Peng Chen (pengchzn@gmail.com) ''' -import sys, os.path as osp +import os.path as osp +import sys + sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__)))) from include import * +""" 基于环形数组实现的队列 """ +class ArrayQueue: + def __init__(self, size): + self.nums = [None] * size # 用于存储队列元素的数组 + self.front = 0 # 头指针，指向队首 + self.rear = 0 # 尾指针，指向队尾 + 1 + + """ 获取队列的容量 """ + def capacity(self): + return len(self.nums) + + """ 获取队列的长度 """ + def size(self): + # 由于将数组看作为环形，可能 rear < front ，因此需要取余数 + return (self.capacity() + self.rear - self.front) % self.capacity() + + """ 判断队列是否为空 """ + def is_empty(self): + return len(self.nums)==0 + + """ 入队 """ + def put(self, val): + if self.size() == self.capacity(): + print("队列已满") + return False + # 尾结点后添加 num + self.nums[self.rear] = val + # 尾指针向后移动一位，越过尾部后返回到数组头部 + self.rear = (self.rear + 1) % self.capacity() + + """ 出队 """ + def get(self): + # 删除头结点 + if self.is_empty(): + print("队列为空") + return False + num = self.nums[self.front] + self.nums[self.front] = None + # 队头指针向后移动，越过尾部后返回到数组头部 + self.front = (self.front + 1) % self.capacity() + return num + + """ 访问队首元素 """ + def peek(self): + # 删除头结点 + if self.is_empty(): + return 1 + return self.nums[self.front] + + """ 访问指定位置元素 """ + def get_index(self, index): + if index >= self.size(): + return -1 + return self.nums[(self.front + index) % self.capacity()] + +if __name__ == "__main__": + """ 初始化队列 """ + queue = ArrayQueue(5) + + """ 元素入队 """ + queue.put(1) + queue.put(3) + queue.put(2) + queue.put(5) + queue.put(4) + print("队列 queue = ", queue.nums) + + """ 访问队首元素 """ + peek = queue.peek() + print("队首元素 peek = ", peek) + + """ 元素出队 """ + get = queue.get() + print("出队元素 get = ", get) + print("出队后 queue = ", queue.nums) + + """ 获取队列的长度 """ + size = queue.size() + print("队列长度 size = ", size) + + """ 判断队列是否为空 """ + is_empty = queue.is_empty() + print("队列是否为空 = ", is_empty) diff --git a/codes/python/chapter_stack_and_queue/deque.py b/codes/python/chapter_stack_and_queue/deque.py index 9894975..0bddd0d 100644 --- a/codes/python/chapter_stack_and_queue/deque.py +++ b/codes/python/chapter_stack_and_queue/deque.py @@ -1,10 +1,47 @@ ''' File: deque.py -Created Time: 2022-11-25 -Author: Krahets (krahets@163.com) +Created Time: 2022-11-29 +Author: Peng Chen (pengchzn@gmail.com) ''' -import sys, os.path as osp +import os.path as osp +import sys + sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__)))) from include import * +from collections import deque + +if __name__ == "__main__": + """ 初始化双向队列 """ + duque = deque() + + """ 元素入队 """ + duque.append(2) # 添加至队尾 + duque.append(5) + duque.append(4) + duque.appendleft(3) # 添加至队首 + duque.appendleft(1) + print("双向队列 duque = ", duque) + + """ 访问队首元素 """ + peekFirst = duque[0] # 队首元素 + print("队首元素 peekFirst = ", peekFirst) + peekLast = duque[-1] # 队尾元素 + print("队尾元素 peekLast = ", peekLast) + + """ 元素出队 """ + popFirst = duque.pop() # 队首元素出队 + print("队首出队元素 popFirst= ", popFirst) + print("队首出队后 duque = ", duque) + popLast = duque.popleft() # 队尾元素出队 + print("队尾出队元素 popLast= ", popLast) + print("队尾出队后 duque = ", duque) + + """ 获取队列的长度 """ + size = len(duque) + print("队列长度 size = ", size) + + """ 判断队列是否为空 """ + is_empty = len(duque) == 0 + print("队列是否为空 = ", is_empty) diff --git a/codes/python/chapter_stack_and_queue/linkedlist_queue.py b/codes/python/chapter_stack_and_queue/linkedlist_queue.py index 3606c8a..53f3b9a 100644 --- a/codes/python/chapter_stack_and_queue/linkedlist_queue.py +++ b/codes/python/chapter_stack_and_queue/linkedlist_queue.py @@ -1,10 +1,92 @@ ''' File: linkedlist_queue.py -Created Time: 2022-11-25 -Author: Krahets (krahets@163.com) +Created Time: 2022-11-29 +Author: Peng Chen (pengchzn@gmail.com) ''' -import sys, os.path as osp +import os.path as osp +import sys + sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__)))) from include import * +""" 基于链表实现的队列 """ +class LinkedListQueue: + def __init__(self): + self.__front = 0 # 头结点 front + self.__rear = 0 # 尾结点 rear + self.__size = 0 + + """ 获取队列的长度 """ + def size(self): + return self.__size + + """ 判断队列是否为空 """ + def is_empty(self): + return not self.__front + + """ 入队 """ + def put(self, num): + # 尾结点后添加 num + node = ListNode(num) + # 如果队列为空，则令头、尾结点都指向该结点 + if self.__front == 0: + self.__front = node + self.__rear = node + # 如果队列不为空，则将该结点添加到尾结点后 + else: + self.__rear.next = node + self.__rear = node + self.__size += 1 + + """ 出队 """ + def get(self): + num = self.peek() + # 删除头结点 + self.__front = self.__front.next + self.__size -= 1 + return num + + """ 访问队首元素 """ + def peek(self): + if self.size() == 0: + return -1 + return self.__front.val + + def to_array(self): + queue = [] + temp = self.__front + while temp: + queue.append(temp.val) + temp = temp.next + return queue + + +if __name__ == "__main__": + """ 初始化队列 """ + queue = LinkedListQueue() + + """ 元素入队 """ + queue.put(1) + queue.put(3) + queue.put(2) + queue.put(5) + queue.put(4) + print("队列 queue = ", queue.to_array()) + + """ 访问队首元素 """ + peek = queue.peek() + print("队首元素 front = ", peek) + + """ 元素出队 """ + get = queue.get() + print("出队元素 get = ", get) + print("出队后 queue = ", queue.to_array()) + + """ 获取队列的长度 """ + size = queue.size() + print("队列长度 size = ", size) + + """ 判断队列是否为空 """ + is_empty = queue.is_empty() + print("队列是否为空 = ", is_empty) diff --git a/codes/python/chapter_stack_and_queue/queue.py b/codes/python/chapter_stack_and_queue/queue.py index 52855b2..3f39d2d 100644 --- a/codes/python/chapter_stack_and_queue/queue.py +++ b/codes/python/chapter_stack_and_queue/queue.py @@ -1,10 +1,42 @@ ''' File: queue.py -Created Time: 2022-11-25 -Author: Krahets (krahets@163.com) +Created Time: 2022-11-29 +Author: Peng Chen (pengchzn@gmail.com) ''' -import sys, os.path as osp +import os.path as osp +import sys + sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__)))) from include import * +import queue + +if __name__ == "__main__": + """ 初始化队列 """ + queue = queue.Queue() + + """ 元素入队 """ + queue.put(1) + queue.put(3) + queue.put(2) + queue.put(5) + queue.put(4) + print("队列 queue = ", queue.queue) + + """ 访问队首元素 """ + peek = queue.queue[0] + print("队首元素 peek = ", peek) + + """ 元素出队 """ + get = queue.get() + print("出队元素 get = ", get) + print("出队后 queue = ", queue.queue) + + """ 获取队列的长度 """ + size = queue.qsize() + print("队列长度 size = ", size) + + """ 判断队列是否为空 """ + is_empty = queue.empty() + print("队列是否为空 = ", is_empty) From 6879f7dc219fe6be156927210a4f73ef1b0e5618 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E5=BD=AD=E7=90=9B?= <66410605+pengchzn@users.noreply.github.com> Date: Thu, 1 Dec 2022 06:50:25 +0800 Subject: [PATCH 2/7] Update array_stack.py An type error of ";" --- codes/python/chapter_stack_and_queue/array_stack.py | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/codes/python/chapter_stack_and_queue/array_stack.py b/codes/python/chapter_stack_and_queue/array_stack.py index b1640a0..23e4b4b 100644 --- a/codes/python/chapter_stack_and_queue/array_stack.py +++ b/codes/python/chapter_stack_and_queue/array_stack.py @@ -60,8 +60,8 @@ if __name__ == "__main__": print("栈顶元素 peek =", peek) """ 访问索引 index 处元素 """ - num = stack.get(3); - print("栈索引 3 处的元素为 num =", num); + num = stack.get(3) + print("栈索引 3 处的元素为 num =", num) """ 元素出栈 """ pop = stack.pop() @@ -74,4 +74,4 @@ if __name__ == "__main__": """ 判断是否为空 """ is_empty = stack.is_empty() - print("栈是否为空 =", is_empty) \ No newline at end of file + print("栈是否为空 =", is_empty) From 59e46ada826ec0588e59f386c0a13da2fa741d7f Mon Sep 17 00:00:00 2001 From: pengchzn Date: Thu, 1 Dec 2022 06:53:08 +0800 Subject: [PATCH 3/7] Add python code for queue --- .../chapter_stack_and_queue/array_queue.py | 53 ++++++++++++------- codes/python/chapter_stack_and_queue/deque.py | 8 +-- .../linkedlist_queue.py | 12 +++-- 3 files changed, 45 insertions(+), 28 deletions(-) diff --git a/codes/python/chapter_stack_and_queue/array_queue.py b/codes/python/chapter_stack_and_queue/array_queue.py index 0e173fe..c4284d8 100644 --- a/codes/python/chapter_stack_and_queue/array_queue.py +++ b/codes/python/chapter_stack_and_queue/array_queue.py @@ -1,6 +1,6 @@ ''' File: array_queue.py -Created Time: 2022-11-29 +Created Time: 2022-12-01 Author: Peng Chen (pengchzn@gmail.com) ''' @@ -13,22 +13,22 @@ from include import * """ 基于环形数组实现的队列 """ class ArrayQueue: def __init__(self, size): - self.nums = [None] * size # 用于存储队列元素的数组 - self.front = 0 # 头指针，指向队首 - self.rear = 0 # 尾指针，指向队尾 + 1 + self.__nums = [None] * size # 用于存储队列元素的数组 + self.__front = 0 # 头指针，指向队首 + self.__rear = 0 # 尾指针，指向队尾 + 1 """ 获取队列的容量 """ def capacity(self): - return len(self.nums) + return len(self.__nums) """ 获取队列的长度 """ def size(self): # 由于将数组看作为环形，可能 rear < front ，因此需要取余数 - return (self.capacity() + self.rear - self.front) % self.capacity() + return (self.capacity() + self.__rear - self.__front) % self.capacity() """ 判断队列是否为空 """ def is_empty(self): - return len(self.nums)==0 + return (self.__rear - self.__front) == 0 """ 入队 """ def put(self, val): @@ -36,9 +36,9 @@ class ArrayQueue: print("队列已满") return False # 尾结点后添加 num - self.nums[self.rear] = val + self.__nums[self.__rear] = val # 尾指针向后移动一位，越过尾部后返回到数组头部 - self.rear = (self.rear + 1) % self.capacity() + self.__rear = (self.__rear + 1) % self.capacity() """ 出队 """ def get(self): @@ -46,28 +46,39 @@ class ArrayQueue: if self.is_empty(): print("队列为空") return False - num = self.nums[self.front] - self.nums[self.front] = None + num = self.__nums[self.__front] # 队头指针向后移动，越过尾部后返回到数组头部 - self.front = (self.front + 1) % self.capacity() + self.__front = (self.__front + 1) % self.capacity() return num """ 访问队首元素 """ def peek(self): # 删除头结点 if self.is_empty(): - return 1 - return self.nums[self.front] + print("队列为空") + return False + return self.__nums[self.__front] """ 访问指定位置元素 """ def get_index(self, index): if index >= self.size(): - return -1 - return self.nums[(self.front + index) % self.capacity()] + print("索引越界") + return False + return self.__nums[(self.__front + index) % self.capacity()] + + """ 返回列表用于打印 """ + def to_list(self): + res = [None] * self.size() + j = self.__front + for i in range(self.size()): + res[i] = self.__nums[(j % self.capacity())] + j += 1 + return res + if __name__ == "__main__": """ 初始化队列 """ - queue = ArrayQueue(5) + queue = ArrayQueue(10) """ 元素入队 """ queue.put(1) @@ -75,16 +86,20 @@ if __name__ == "__main__": queue.put(2) queue.put(5) queue.put(4) - print("队列 queue = ", queue.nums) + print("队列 queue = ", queue.to_list()) """ 访问队首元素 """ peek = queue.peek() print("队首元素 peek = ", peek) + """ 访问索引 index 处元素 """ + num = queue.get_index(3) + print("队列索引 3 处的元素为 num =", num) + """ 元素出队 """ get = queue.get() print("出队元素 get = ", get) - print("出队后 queue = ", queue.nums) + print("出队后 queue = ", queue.to_list()) """ 获取队列的长度 """ size = queue.size() diff --git a/codes/python/chapter_stack_and_queue/deque.py b/codes/python/chapter_stack_and_queue/deque.py index 0bddd0d..a2929df 100644 --- a/codes/python/chapter_stack_and_queue/deque.py +++ b/codes/python/chapter_stack_and_queue/deque.py @@ -38,10 +38,10 @@ if __name__ == "__main__": print("队尾出队元素 popLast= ", popLast) print("队尾出队后 duque = ", duque) - """ 获取队列的长度 """ + """ 获取双向队列的长度 """ size = len(duque) - print("队列长度 size = ", size) + print("双向队列长度 size = ", size) - """ 判断队列是否为空 """ + """ 判断双向队列是否为空 """ is_empty = len(duque) == 0 - print("队列是否为空 = ", is_empty) + print("双向队列是否为空 = ", is_empty) diff --git a/codes/python/chapter_stack_and_queue/linkedlist_queue.py b/codes/python/chapter_stack_and_queue/linkedlist_queue.py index 53f3b9a..d5a2202 100644 --- a/codes/python/chapter_stack_and_queue/linkedlist_queue.py +++ b/codes/python/chapter_stack_and_queue/linkedlist_queue.py @@ -1,6 +1,6 @@ ''' File: linkedlist_queue.py -Created Time: 2022-11-29 +Created Time: 2022-12-01 Author: Peng Chen (pengchzn@gmail.com) ''' @@ -50,10 +50,12 @@ class LinkedListQueue: """ 访问队首元素 """ def peek(self): if self.size() == 0: - return -1 + print("队列为空") + return False return self.__front.val - def to_array(self): + """ 转化为列表用于打印 """ + def to_list(self): queue = [] temp = self.__front while temp: @@ -72,7 +74,7 @@ if __name__ == "__main__": queue.put(2) queue.put(5) queue.put(4) - print("队列 queue = ", queue.to_array()) + print("队列 queue = ", queue.to_list()) """ 访问队首元素 """ peek = queue.peek() @@ -81,7 +83,7 @@ if __name__ == "__main__": """ 元素出队 """ get = queue.get() print("出队元素 get = ", get) - print("出队后 queue = ", queue.to_array()) + print("出队后 queue = ", queue.to_list()) """ 获取队列的长度 """ size = queue.size() From 84825a22d9b64a2e02dffbb0dcdc3535b1072606 Mon Sep 17 00:00:00 2001 From: mgisr Date: Thu, 1 Dec 2022 09:09:34 +0800 Subject: [PATCH 4/7] fix(codes/cpp/include/TreeNode.hpp): Fix 'vecToTree' function --- codes/cpp/include/TreeNode.hpp | 31 +++++++++++++++++-------------- 1 file changed, 17 insertions(+), 14 deletions(-) diff --git a/codes/cpp/include/TreeNode.hpp b/codes/cpp/include/TreeNode.hpp index 614d799..7be2b8d 100644 --- a/codes/cpp/include/TreeNode.hpp +++ b/codes/cpp/include/TreeNode.hpp @@ -23,25 +23,28 @@ struct TreeNode { * @param list * @return TreeNode* */ -TreeNode* vecToTree(vector list) { - TreeNode *root = new TreeNode(list[0]); - queue que; - que.emplace(root); - int i = 1; - while(!que.empty()) { - TreeNode *node = que.front(); +TreeNode *vecToTree(vector list) { + if (list.empty()) { + return nullptr; + } + + auto *root = new TreeNode(list[0]); + queue que; + size_t n = list.size(), index = 1; + while (index < n) { + auto node = que.front(); que.pop(); - if(list[i] != INT_MAX) { - node->left = new TreeNode(list[i]); + + if (index < n) { + node->left = new TreeNode(list[index++]); que.emplace(node->left); } - i++; - if(list[i] != INT_MAX) { - node->right = new TreeNode(list[i]); + if (index < n) { + node->right = new TreeNode(list[index++]); que.emplace(node->right); } - i++; } + return root; } @@ -52,7 +55,7 @@ TreeNode* vecToTree(vector list) { * @param val * @return TreeNode* */ -TreeNode* getTreeNode(TreeNode *root, int val) { +TreeNode *getTreeNode(TreeNode *root, int val) { if (root == nullptr) return nullptr; if (root->val == val) From 7eea137c28a767dd6deb96af163d29ee883950de Mon Sep 17 00:00:00 2001 From: IsChristina <315644507@qq.com> Date: Thu, 1 Dec 2022 18:28:57 +0800 Subject: [PATCH 5/7] add sort for javascript codes --- .../javascript/chapter_sorting/bubble_sort.js | 49 ++++++ .../chapter_sorting/insertion_sort.js | 24 +++ .../javascript/chapter_sorting/merge_sort.js | 51 ++++++ .../javascript/chapter_sorting/quick_sort.js | 157 ++++++++++++++++++ docs/chapter_sorting/bubble_sort.md | 44 +++++ docs/chapter_sorting/insertion_sort.md | 18 ++ docs/chapter_sorting/merge_sort.md | 45 +++++ docs/chapter_sorting/quick_sort.md | 91 ++++++++++ 8 files changed, 479 insertions(+) create mode 100644 codes/javascript/chapter_sorting/bubble_sort.js create mode 100644 codes/javascript/chapter_sorting/insertion_sort.js create mode 100644 codes/javascript/chapter_sorting/merge_sort.js create mode 100644 codes/javascript/chapter_sorting/quick_sort.js diff --git a/codes/javascript/chapter_sorting/bubble_sort.js b/codes/javascript/chapter_sorting/bubble_sort.js new file mode 100644 index 0000000..270565c --- /dev/null +++ b/codes/javascript/chapter_sorting/bubble_sort.js @@ -0,0 +1,49 @@ +/** + * File: quick_sort.js + * Created Time: 2022-12-01 + * Author: IsChristina (christinaxia77@foxmail.com) + */ + +/* 冒泡排序 */ +function bubbleSort(nums) { + // 外循环：待排序元素数量为 n-1, n-2, ..., 1 + for (let i = nums.length - 1; i > 0; i--) { + // 内循环：冒泡操作 + for (let j = 0; j < i; j++) { + if (nums[j] > nums[j + 1]) { + // 交换 nums[j] 与 nums[j + 1] + let tmp = nums[j]; + nums[j] = nums[j + 1]; + nums[j + 1] = tmp; + } + } + } +} + +/* 冒泡排序（标志优化）*/ +function bubbleSortWithFlag(nums) { + // 外循环：待排序元素数量为 n-1, n-2, ..., 1 + for (let i = nums.length - 1; i > 0; i--) { + let flag = false; // 初始化标志位 + // 内循环：冒泡操作 + for (let j = 0; j < i; j++) { + if (nums[j] > nums[j + 1]) { + // 交换 nums[j] 与 nums[j + 1] + let tmp = nums[j]; + nums[j] = nums[j + 1]; + nums[j + 1] = tmp; + flag = true; // 记录交换元素 + } + } + if (!flag) break; // 此轮冒泡未交换任何元素，直接跳出 + } +} + +/* Driver Code */ +var nums = [4, 1, 3, 1, 5, 2] +bubbleSort(nums) +console.log("排序后数组 nums =", nums) + +var nums1 = [4, 1, 3, 1, 5, 2] +bubbleSortWithFlag(nums1) +console.log("排序后数组 nums =", nums1) \ No newline at end of file diff --git a/codes/javascript/chapter_sorting/insertion_sort.js b/codes/javascript/chapter_sorting/insertion_sort.js new file mode 100644 index 0000000..2ba7155 --- /dev/null +++ b/codes/javascript/chapter_sorting/insertion_sort.js @@ -0,0 +1,24 @@ +/** + * File: quick_sort.js + * Created Time: 2022-12-01 + * Author: IsChristina (christinaxia77@foxmail.com) + */ + +/* 插入排序 */ +function insertionSort(nums) { + // 外循环：base = nums[1], nums[2], ..., nums[n-1] + for (let i = 1; i < nums.length; i++) { + let base = nums[i], j = i - 1; + // 内循环：将 base 插入到左边的正确位置 + while (j >= 0 && nums[j] > base) { + nums[j + 1] = nums[j]; // 1. 将 nums[j] 向右移动一位 + j--; + } + nums[j + 1] = base; // 2. 将 base 赋值到正确位置 + } +} + +/* Driver Code */ +var nums = [4, 1, 3, 1, 5, 2] +insertionSort(nums) +console.log("排序后数组 nums = ", nums) \ No newline at end of file diff --git a/codes/javascript/chapter_sorting/merge_sort.js b/codes/javascript/chapter_sorting/merge_sort.js new file mode 100644 index 0000000..635cc1d --- /dev/null +++ b/codes/javascript/chapter_sorting/merge_sort.js @@ -0,0 +1,51 @@ +/** + * File: quick_sort.js + * Created Time: 2022-12-01 + * Author: IsChristina (christinaxia77@foxmail.com) + */ + +/** +* 合并左子数组和右子数组 +* 左子数组区间 [left, mid] +* 右子数组区间 [mid + 1, right] +*/ +function merge(nums, left, mid, right) { + // 初始化辅助数组 + let tmp = nums.slice(left, right + 1); + // 左子数组的起始索引和结束索引 + let leftStart = left - left, leftEnd = mid - left; + // 右子数组的起始索引和结束索引 + let rightStart = mid + 1 - left, rightEnd = right - left; + // i, j 分别指向左子数组、右子数组的首元素 + let i = leftStart, j = rightStart; + // 通过覆盖原数组 nums 来合并左子数组和右子数组 + for (let k = left; k <= right; k++) { + // 若 “左子数组已全部合并完”，则选取右子数组元素，并且 j++ + if (i > leftEnd) { + nums[k] = tmp[j++]; + // 否则，若 “右子数组已全部合并完” 或 “左子数组元素 < 右子数组元素”，则选取左子数组元素，并且 i++ + } else if (j > rightEnd || tmp[i] <= tmp[j]) { + nums[k] = tmp[i++]; + // 否则，若 “左子数组元素 > 右子数组元素”，则选取右子数组元素，并且 j++ + } else { + nums[k] = tmp[j++]; + } + } +} + +/* 归并排序 */ +function mergeSort(nums, left, right) { + // 终止条件 + if (left >= right) return; // 当子数组长度为 1 时终止递归 + // 划分阶段 + let mid = Math.floor((left + right) / 2); // 计算中点 + mergeSort(nums, left, mid); // 递归左子数组 + mergeSort(nums, mid + 1, right); // 递归右子数组 + // 合并阶段 + merge(nums, left, mid, right); +} + +/* Driver Code */ +var nums = [ 7, 3, 2, 6, 0, 1, 5, 4 ] +mergeSort(nums, 0, nums.length - 1) +console.log("归并排序完成后 nums =", nums) \ No newline at end of file diff --git a/codes/javascript/chapter_sorting/quick_sort.js b/codes/javascript/chapter_sorting/quick_sort.js new file mode 100644 index 0000000..bad6fa7 --- /dev/null +++ b/codes/javascript/chapter_sorting/quick_sort.js @@ -0,0 +1,157 @@ +/** + * File: quick_sort.js + * Created Time: 2022-12-01 + * Author: IsChristina (christinaxia77@foxmail.com) + */ + +/* 快速排序类 */ +class QuickSort { + /* 元素交换 */ + swap(nums, i, j) { + let tmp = nums[i] + nums[i] = nums[j] + nums[j] = tmp + } + + /* 哨兵划分 */ + partition(nums, left, right){ + // 以 nums[left] 作为基准数 + let i = left, j = right + while(i < j){ + while(i < j && nums[j] >= nums[left]){ + j -= 1 // 从右向左找首个小于基准数的元素 + } + while(i < j && nums[i] <= nums[left]){ + i += 1 // 从左向右找首个大于基准数的元素 + } + // 元素交换 + this.swap(nums, i, j) // 交换这两个元素 + } + this.swap(nums, i, left) // 将基准数交换至两子数组的分界线 + return i // 返回基准数的索引 + } + + /* 快速排序 */ + quickSort(nums, left, right){ + // 子数组长度为 1 时终止递归 + if(left >= right) return + // 哨兵划分 + const pivot = this.partition(nums, left, right) + // 递归左子数组、右子数组 + this.quickSort(nums, left, pivot - 1) + this.quickSort(nums, pivot + 1, right) + } +} + +/* 快速排序类（中位基准数优化） */ +class QuickSortMedian { + /* 元素交换 */ + swap(nums, i, j) { + let tmp = nums[i] + nums[i] = nums[j] + nums[j] = tmp + } + + /* 选取三个元素的中位数 */ + medianThree(nums, left, mid, right) { + // 使用了异或操作来简化代码 + // 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1 + if ((nums[left] > nums[mid]) ^ (nums[left] > nums[right])) + return left; + else if ((nums[mid] < nums[left]) ^ (nums[mid] < nums[right])) + return mid; + else + return right; + } + + /* 哨兵划分（三数取中值） */ + partition(nums, left, right) { + // 选取三个候选元素的中位数 + let med = this.medianThree(nums, left, Math.floor((left + right) / 2), right); + // 将中位数交换至数组最左端 + this.swap(nums, left, med); + // 以 nums[left] 作为基准数 + let i = left, j = right; + while (i < j) { + while (i < j && nums[j] >= nums[left]) + j--; // 从右向左找首个小于基准数的元素 + while (i < j && nums[i] <= nums[left]) + i++; // 从左向右找首个大于基准数的元素 + this.swap(nums, i, j); // 交换这两个元素 + } + this.swap(nums, i, left); // 将基准数交换至两子数组的分界线 + return i; // 返回基准数的索引 + } + + /* 快速排序 */ + quickSort(nums, left, right) { + // 子数组长度为 1 时终止递归 + if (left >= right) return; + // 哨兵划分 + const pivot = this.partition(nums, left, right); + // 递归左子数组、右子数组 + this.quickSort(nums, left, pivot - 1); + this.quickSort(nums, pivot + 1, right); + } +} + +/* 快速排序类（尾递归优化） */ +class QuickSortTailCall { + /* 元素交换 */ + swap(nums, i, j) { + let tmp = nums[i] + nums[i] = nums[j] + nums[j] = tmp + } + + /* 哨兵划分 */ + partition(nums, left, right) { + // 以 nums[left] 作为基准数 + let i = left, j = right; + while (i < j) { + while (i < j && nums[j] >= nums[left]) + j--; // 从右向左找首个小于基准数的元素 + while (i < j && nums[i] <= nums[left]) + i++; // 从左向右找首个大于基准数的元素 + this.swap(nums, i, j); // 交换这两个元素 + } + this.swap(nums, i, left); // 将基准数交换至两子数组的分界线 + return i; // 返回基准数的索引 + } + + /* 快速排序（尾递归优化） */ + quickSort(nums, left, right) { + // 子数组长度为 1 时终止 + while (left < right) { + // 哨兵划分操作 + let pivot = this.partition(nums, left, right); + // 对两个子数组中较短的那个执行快排 + if (pivot - left < right - pivot) { + this.quickSort(nums, left, pivot - 1); // 递归排序左子数组 + left = pivot + 1; // 剩余待排序区间为 [pivot + 1, right] + } else { + this.quickSort(nums, pivot + 1, right); // 递归排序右子数组 + right = pivot - 1; // 剩余待排序区间为 [left, pivot - 1] + } + } + } +} + +/* Driver Code */ +/* 快速排序 */ +var nums = [4, 1, 3, 1, 5, 2] +var quickSort = new QuickSort() +quickSort.quickSort(nums, 0, nums.length - 1) +console.log("快速排序完成后 nums =", nums) + +/* 快速排序（中位基准数优化） */ +nums1 = [4, 1, 3, 1, 5,2] +var quickSortMedian = new QuickSort() +quickSortMedian.quickSort(nums1, 0, nums1.length - 1) +console.log("快速排序（中位基准数优化）完成后 nums =", nums1) + +/* 快速排序（尾递归优化） */ +nums2 = [4, 1, 3, 1, 5, 2] +var quickSortTailCall = new QuickSort() +quickSortTailCall.quickSort(nums2, 0, nums2.length - 1) +console.log("快速排序（尾递归优化）完成后 nums =", nums2) \ No newline at end of file diff --git a/docs/chapter_sorting/bubble_sort.md b/docs/chapter_sorting/bubble_sort.md index 3f35ea1..fe1d071 100644 --- a/docs/chapter_sorting/bubble_sort.md +++ b/docs/chapter_sorting/bubble_sort.md @@ -73,6 +73,27 @@ comments: true } } ``` + +=== "JavaScript" + + ```js title="bubble_sort.js" + /* 冒泡排序 */ + function bubbleSort(nums) { + // 外循环：待排序元素数量为 n-1, n-2, ..., 1 + for (let i = nums.length - 1; i > 0; i--) { + // 内循环：冒泡操作 + for (let j = 0; j < i; j++) { + if (nums[j] > nums[j + 1]) { + // 交换 nums[j] 与 nums[j + 1] + let tmp = nums[j]; + nums[j] = nums[j + 1]; + nums[j + 1] = tmp; + } + } + } + } + ``` + === "C++" ```cpp title="bubble_sort.cpp" @@ -149,6 +170,29 @@ comments: true } ``` +=== "JavaScript" + + ```js title="bubble_sort.js" + /* 冒泡排序（标志优化）*/ + function bubbleSortWithFlag(nums) { + // 外循环：待排序元素数量为 n-1, n-2, ..., 1 + for (let i = nums.length - 1; i > 0; i--) { + let flag = false; // 初始化标志位 + // 内循环：冒泡操作 + for (let j = 0; j < i; j++) { + if (nums[j] > nums[j + 1]) { + // 交换 nums[j] 与 nums[j + 1] + let tmp = nums[j]; + nums[j] = nums[j + 1]; + nums[j + 1] = tmp; + flag = true; // 记录交换元素 + } + } + if (!flag) break; // 此轮冒泡未交换任何元素，直接跳出 + } + } + ``` + === "C++" ```cpp title="bubble_sort.cpp" diff --git a/docs/chapter_sorting/insertion_sort.md b/docs/chapter_sorting/insertion_sort.md index c9563fc..e220c2e 100644 --- a/docs/chapter_sorting/insertion_sort.md +++ b/docs/chapter_sorting/insertion_sort.md @@ -42,6 +42,24 @@ comments: true } ``` +=== "JavaScript" + + ```js title="insertion_sort.js" + /* 插入排序 */ + function insertionSort(nums) { + // 外循环：base = nums[1], nums[2], ..., nums[n-1] + for (let i = 1; i < nums.length; i++) { + let base = nums[i], j = i - 1; + // 内循环：将 base 插入到左边的正确位置 + while (j >= 0 && nums[j] > base) { + nums[j + 1] = nums[j]; // 1. 将 nums[j] 向右移动一位 + j--; + } + nums[j + 1] = base; // 2. 将 base 赋值到正确位置 + } + } + ``` + === "C++" ```cpp title="insertion_sort.cpp" diff --git a/docs/chapter_sorting/merge_sort.md b/docs/chapter_sorting/merge_sort.md index 00df177..58a48c2 100644 --- a/docs/chapter_sorting/merge_sort.md +++ b/docs/chapter_sorting/merge_sort.md @@ -103,6 +103,51 @@ comments: true } ``` +=== "JavaScript" + + ```js title="merge_sort.js" + /** + * 合并左子数组和右子数组 + * 左子数组区间 [left, mid] + * 右子数组区间 [mid + 1, right] + */ + function merge(nums, left, mid, right) { + // 初始化辅助数组 + let tmp = nums.slice(left, right + 1); + // 左子数组的起始索引和结束索引 + let leftStart = left - left, leftEnd = mid - left; + // 右子数组的起始索引和结束索引 + let rightStart = mid + 1 - left, rightEnd = right - left; + // i, j 分别指向左子数组、右子数组的首元素 + let i = leftStart, j = rightStart; + // 通过覆盖原数组 nums 来合并左子数组和右子数组 + for (let k = left; k <= right; k++) { + // 若 “左子数组已全部合并完”，则选取右子数组元素，并且 j++ + if (i > leftEnd) { + nums[k] = tmp[j++]; + // 否则，若 “右子数组已全部合并完” 或 “左子数组元素 < 右子数组元素”，则选取左子数组元素，并且 i++ + } else if (j > rightEnd || tmp[i] <= tmp[j]) { + nums[k] = tmp[i++]; + // 否则，若 “左子数组元素 > 右子数组元素”，则选取右子数组元素，并且 j++ + } else { + nums[k] = tmp[j++]; + } + } + } + + /* 归并排序 */ + function mergeSort(nums, left, right) { + // 终止条件 + if (left >= right) return; // 当子数组长度为 1 时终止递归 + // 划分阶段 + let mid = Math.floor((left + right) / 2); // 计算中点 + mergeSort(nums, left, mid); // 递归左子数组 + mergeSort(nums, mid + 1, right); // 递归右子数组 + // 合并阶段 + merge(nums, left, mid, right); + } + ``` + === "C++" ```cpp title="merge_sort.cpp" diff --git a/docs/chapter_sorting/quick_sort.md b/docs/chapter_sorting/quick_sort.md index c9488f1..f931e06 100644 --- a/docs/chapter_sorting/quick_sort.md +++ b/docs/chapter_sorting/quick_sort.md @@ -61,6 +61,35 @@ comments: true } ``` +=== "JavaScript" + + ``` js title="quick_sort.js" + /* 元素交换 */ + function swap(nums, i, j) { + let tmp = nums[i] + nums[i] = nums[j] + nums[j] = tmp + } + + /* 哨兵划分 */ + function partition(nums, left, right){ + // 以 nums[left] 作为基准数 + let i = left, j = right + while(i < j){ + while(i < j && nums[j] >= nums[left]){ + j -= 1 // 从右向左找首个小于基准数的元素 + } + while(i < j && nums[i] <= nums[left]){ + i += 1 // 从左向右找首个大于基准数的元素 + } + // 元素交换 + swap(nums, i, j) // 交换这两个元素 + } + swap(nums, i, left) // 将基准数交换至两子数组的分界线 + return i // 返回基准数的索引 + } + ``` + === "C++" ```cpp title="quick_sort.cpp" @@ -138,6 +167,21 @@ comments: true } ``` +=== "JavaScript" + + ```js title="quick_sort.js" + /* 快速排序 */ + function quickSort(nums, left, right){ + // 子数组长度为 1 时终止递归 + if(left >= right) return + // 哨兵划分 + const pivot = partition(nums, left, right) + // 递归左子数组、右子数组 + quick_sort(nums, left, pivot - 1) + quick_sort(nums, pivot + 1, right) + } + ``` + === "C++" ```cpp title="quick_sort.cpp" @@ -225,6 +269,32 @@ comments: true } ``` +=== "JavaScript" + + ```js title="quick_sort.js" + /* 选取三个元素的中位数 */ + function medianThree(nums, left, mid, right) { + // 使用了异或操作来简化代码 + // 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1 + if ((nums[left] > nums[mid]) ^ (nums[left] > nums[right])) + return left; + else if ((nums[mid] < nums[left]) ^ (nums[mid] < nums[right])) + return mid; + else + return right; + } + + /* 哨兵划分（三数取中值） */ + function partition(nums, left, right) { + // 选取三个候选元素的中位数 + let med = medianThree(nums, left, Math.floor((left + right) / 2), right); + // 将中位数交换至数组最左端 + swap(nums, left, med); + // 以 nums[left] 作为基准数 + // 下同省略... + } + ``` + === "C++" ```cpp title="quick_sort.cpp" @@ -301,6 +371,27 @@ comments: true } ``` +=== "JavaScript" + + ```js title="quick_sort.js" + /* 快速排序（尾递归优化） */ + quickSort(nums, left, right) { + // 子数组长度为 1 时终止 + while (left < right) { + // 哨兵划分操作 + let pivot = partition(nums, left, right); + // 对两个子数组中较短的那个执行快排 + if (pivot - left < right - pivot) { + quickSort(nums, left, pivot - 1); // 递归排序左子数组 + left = pivot + 1; // 剩余待排序区间为 [pivot + 1, right] + } else { + quickSort(nums, pivot + 1, right); // 递归排序右子数组 + right = pivot - 1; // 剩余待排序区间为 [left, pivot - 1] + } + } + } + ``` + === "C++" ```cpp title="quick_sort.cpp" From be8a586768ed246bd0278481a6d16ba80d5ec6d4 Mon Sep 17 00:00:00 2001 From: Yudong Jin Date: Thu, 1 Dec 2022 22:38:01 +0800 Subject: [PATCH 6/7] Update quick_sort.js Fix indentation --- .../javascript/chapter_sorting/quick_sort.js | 38 +++++++++---------- 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/codes/javascript/chapter_sorting/quick_sort.js b/codes/javascript/chapter_sorting/quick_sort.js index bad6fa7..405bf76 100644 --- a/codes/javascript/chapter_sorting/quick_sort.js +++ b/codes/javascript/chapter_sorting/quick_sort.js @@ -17,29 +17,29 @@ class QuickSort { partition(nums, left, right){ // 以 nums[left] 作为基准数 let i = left, j = right - while(i < j){ - while(i < j && nums[j] >= nums[left]){ - j -= 1 // 从右向左找首个小于基准数的元素 - } - while(i < j && nums[i] <= nums[left]){ - i += 1 // 从左向右找首个大于基准数的元素 - } - // 元素交换 - this.swap(nums, i, j) // 交换这两个元素 + while(i < j){ + while(i < j && nums[j] >= nums[left]){ + j -= 1 // 从右向左找首个小于基准数的元素 } - this.swap(nums, i, left) // 将基准数交换至两子数组的分界线 - return i // 返回基准数的索引 + while(i < j && nums[i] <= nums[left]){ + i += 1 // 从左向右找首个大于基准数的元素 + } + // 元素交换 + this.swap(nums, i, j) // 交换这两个元素 + } + this.swap(nums, i, left) // 将基准数交换至两子数组的分界线 + return i // 返回基准数的索引 } /* 快速排序 */ quickSort(nums, left, right){ - // 子数组长度为 1 时终止递归 - if(left >= right) return - // 哨兵划分 - const pivot = this.partition(nums, left, right) - // 递归左子数组、右子数组 - this.quickSort(nums, left, pivot - 1) - this.quickSort(nums, pivot + 1, right) + // 子数组长度为 1 时终止递归 + if(left >= right) return + // 哨兵划分 + const pivot = this.partition(nums, left, right) + // 递归左子数组、右子数组 + this.quickSort(nums, left, pivot - 1) + this.quickSort(nums, pivot + 1, right) } } @@ -154,4 +154,4 @@ console.log("快速排序（中位基准数优化）完成后 nums =", nums1) nums2 = [4, 1, 3, 1, 5, 2] var quickSortTailCall = new QuickSort() quickSortTailCall.quickSort(nums2, 0, nums2.length - 1) -console.log("快速排序（尾递归优化）完成后 nums =", nums2) \ No newline at end of file +console.log("快速排序（尾递归优化）完成后 nums =", nums2) From 1728be1e61289f88ad186d72e05c89019e558d3b Mon Sep 17 00:00:00 2001 From: Yudong Jin Date: Thu, 1 Dec 2022 22:39:31 +0800 Subject: [PATCH 7/7] Update quick_sort.md Fix indentation --- docs/chapter_sorting/quick_sort.md | 36 +++++++++++++++--------------- 1 file changed, 18 insertions(+), 18 deletions(-) diff --git a/docs/chapter_sorting/quick_sort.md b/docs/chapter_sorting/quick_sort.md index f931e06..a0df18e 100644 --- a/docs/chapter_sorting/quick_sort.md +++ b/docs/chapter_sorting/quick_sort.md @@ -75,18 +75,18 @@ comments: true function partition(nums, left, right){ // 以 nums[left] 作为基准数 let i = left, j = right - while(i < j){ - while(i < j && nums[j] >= nums[left]){ - j -= 1 // 从右向左找首个小于基准数的元素 - } - while(i < j && nums[i] <= nums[left]){ - i += 1 // 从左向右找首个大于基准数的元素 - } - // 元素交换 - swap(nums, i, j) // 交换这两个元素 + while(i < j){ + while(i < j && nums[j] >= nums[left]){ + j -= 1 // 从右向左找首个小于基准数的元素 } - swap(nums, i, left) // 将基准数交换至两子数组的分界线 - return i // 返回基准数的索引 + while(i < j && nums[i] <= nums[left]){ + i += 1 // 从左向右找首个大于基准数的元素 + } + // 元素交换 + swap(nums, i, j) // 交换这两个元素 + } + swap(nums, i, left) // 将基准数交换至两子数组的分界线 + return i // 返回基准数的索引 } ``` @@ -172,13 +172,13 @@ comments: true ```js title="quick_sort.js" /* 快速排序 */ function quickSort(nums, left, right){ - // 子数组长度为 1 时终止递归 - if(left >= right) return - // 哨兵划分 - const pivot = partition(nums, left, right) - // 递归左子数组、右子数组 - quick_sort(nums, left, pivot - 1) - quick_sort(nums, pivot + 1, right) + // 子数组长度为 1 时终止递归 + if(left >= right) return + // 哨兵划分 + const pivot = partition(nums, left, right) + // 递归左子数组、右子数组 + quick_sort(nums, left, pivot - 1) + quick_sort(nums, pivot + 1, right) } ```