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Update code style for Python

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krahets
2023-03-03 03:07:22 +08:00
parent 7e9e6b000c
commit 7c501140f0
45 changed files with 274 additions and 266 deletions
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6
codes/python/chapter_sorting/bubble_sort.py
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@@ -6,10 +6,10 @@ Author: timi (xisunyy@163.com)
import sys, os.path as osp
sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
from include import *
from modules import *
""" 冒泡排序 """
def bubble_sort(nums):
""" 冒泡排序 """
n = len(nums)
# 外循环：待排序元素数量为 n-1, n-2, ..., 1
for i in range(n - 1, 0, -1):
@@ -19,8 +19,8 @@ def bubble_sort(nums):
# 交换 nums[j] 与 nums[j + 1]
nums[j], nums[j + 1] = nums[j + 1], nums[j]
""" 冒泡排序（标志优化） """
def bubble_sort_with_flag(nums):
""" 冒泡排序（标志优化） """
n = len(nums)
# 外循环：待排序元素数量为 n-1, n-2, ..., 1
for i in range(n - 1, 0, -1):

6
codes/python/chapter_sorting/insertion_sort.py
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@@ -6,11 +6,11 @@ Author: timi (xisunyy@163.com)
import sys, os.path as osp
sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
from include import *
from modules import *
""" 插入排序 """
def insertion_sort(nums):
# 外循环：base = nums[1], nums[2], ..., nums[n-1]
""" 插入排序 """
# 外循环：base = nums[1], nums[2], ..., nums[n-1]
for i in range(1, len(nums)):
base = nums[i]
j = i - 1

11
codes/python/chapter_sorting/merge_sort.py
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@@ -6,13 +6,12 @@ Author: timi (xisunyy@163.com)
import sys, os.path as osp
sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
from include import *
from modules import *
""" 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]
def merge(nums, left, mid, right):
""" 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]
# 初始化辅助数组 借助 copy模块
tmp = nums[left:right + 1]
# 左子数组的起始索引和结束索引
@@ -36,8 +35,8 @@ def merge(nums, left, mid, right):
nums[k] = tmp[j]
j += 1
""" 归并排序 """
def merge_sort(nums, left, right):
""" 归并排序 """
# 终止条件
if left >= right:
return # 当子数组长度为 1 时终止递归

36
codes/python/chapter_sorting/quick_sort.py
View File

@@ -6,12 +6,12 @@ Author: timi (xisunyy@163.com)
import sys, os.path as osp
sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
from include import *
from modules import *
""" 快速排序类 """
class QuickSort:
""" 哨兵划分 """
""" 快速排序类 """
def partition(self, nums, left, right):
""" 哨兵划分 """
# 以 nums[left] 作为基准数
i, j = left, right
while i < j:
@@ -25,8 +25,8 @@ class QuickSort:
nums[i], nums[left] = nums[left], nums[i]
return i # 返回基准数的索引
""" 快速排序 """
def quick_sort(self, nums, left, right):
""" 快速排序 """
# 子数组长度为 1 时终止递归
if left >= right:
return
@@ -36,10 +36,10 @@ class QuickSort:
self.quick_sort(nums, left, pivot - 1)
self.quick_sort(nums, pivot + 1, right)
""" 快速排序类（中位基准数优化）"""
class QuickSortMedian:
""" 选取三个元素的中位数 """
""" 快速排序类（中位基准数优化）"""
def median_three(self, nums, left, mid, right):
""" 选取三个元素的中位数 """
# 此处使用异或运算来简化代码
# 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1
if (nums[left] < nums[mid]) ^ (nums[left] < nums[right]):
@@ -48,8 +48,8 @@ class QuickSortMedian:
return mid
return right
""" 哨兵划分（三数取中值） """
def partition(self, nums, left, right):
""" 哨兵划分（三数取中值） """
# 以 nums[left] 作为基准数
med = self.median_three(nums, left, (left + right) // 2, right)
# 将中位数交换至数组最左端
@@ -67,8 +67,8 @@ class QuickSortMedian:
nums[i], nums[left] = nums[left], nums[i]
return i # 返回基准数的索引
""" 快速排序 """
def quick_sort(self, nums, left, right):
""" 快速排序 """
# 子数组长度为 1 时终止递归
if left >= right: return
# 哨兵划分
@@ -77,10 +77,10 @@ class QuickSortMedian:
self.quick_sort(nums, left, pivot - 1)
self.quick_sort(nums, pivot + 1, right)
""" 快速排序类（尾递归优化） """
class QuickSortTailCall:
""" 哨兵划分 """
""" 快速排序类（尾递归优化） """
def partition(self, nums, left, right):
""" 哨兵划分 """
# 以 nums[left] 作为基准数
i, j = left, right
while i < j:
@@ -92,10 +92,10 @@ class QuickSortTailCall:
nums[i], nums[j] = nums[j], nums[i]
# 将基准数交换至两子数组的分界线
nums[i], nums[left] = nums[left], nums[i]
return i # 返回基准数的索引
return i # 返回基准数的索引
""" 快速排序（尾递归优化） """
def quick_sort(self, nums, left, right):
""" 快速排序（尾递归优化） """
# 子数组长度为 1 时终止
while left < right:
# 哨兵划分操作
@@ -112,16 +112,16 @@ class QuickSortTailCall:
""" Driver Code """
if __name__ == '__main__':
# 快速排序
nums = [4, 1, 3, 1, 5, 2]
nums = [2, 4, 1, 0, 3, 5]
QuickSort().quick_sort(nums, 0, len(nums) - 1)
print("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]
nums1 = [2, 4, 1, 0, 3, 5]
QuickSortMedian().quick_sort(nums1, 0, len(nums1) - 1)
print("快速排序（中位基准数优化）完成后 nums =", nums)
print("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]
QuickSortTailCall().quick_sort(nums, 0, len(nums2) - 1)
print("快速排序（尾递归优化）完成后 nums =", nums)
nums2 = [2, 4, 1, 0, 3, 5]
QuickSortTailCall().quick_sort(nums2, 0, len(nums2) - 1)
print("快速排序（尾递归优化）完成后 nums =", nums2)