氣泡排序：
最優時間複雜度：o(n)
最壞時間複雜度：o(n^2)
穩定性：穩定
def bubble_sort(alist):
"""氣泡排序"""
for j in range(len(alist)-1, 0, -1):
count = 0
for i in range(j):
if alist[i] > alist[i+1]:
alist[i], alist[i+1] = alist[i+1], alist[i]
count += 1
if count == 0:
break
return alist
最優時間複雜度：o(n^2)
最壞時間複雜度：o(n^2)
穩定性：不穩定
def choose_sort(alist):
"""選擇排序"""
for i in range(len(alist)):
min_x = alist[i]
min_pos = i
for j in range(i+1, len(alist)):
if alist[j] < min_x:
min_x = alist[j]
min_pos = j
alist[min_pos], alist[i] = alist[i], alist[min_pos]
return alist
最優時間複雜度：o(n)
最壞時間複雜度：o(n^2)
穩定性：穩定
def insert_sort(alist):
"""插入排序"""
for j in range(1, len(alist)):
for i in range(j, 0, -1):
if alist[i] < alist[i-1]:
alist[i], alist[i-1] = alist[i-1], alist[i]
else:
break
return alist
最優時間複雜度：根據步長而調整
最壞時間複雜度：o(n^2)
穩定性：不穩定
def shell_sort(alist):
"""希爾排序"""
gap = len(alist) // 2
#gap到0之前，插入演算法執行的次數
while gap >= 1:
#插入演算法，與普通插入演算法區別在於gap步長
for j in range(gap, len(alist)):
i = j
while i > 0:
if alist[i] < alist[i-gap]:
alist[i], alist[i-gap] = alist[i-gap], alist[i]
i -= gap
else:
break
#調整步長
gap = gap // 2
return alist
最優時間複雜度：o(nlogn)
最壞時間複雜度：o(n^2)
穩定性：不穩定
def quick_sort(alist, first, last):
"""快速排序"""
if first >= last:
return
low = first
high = last
mid = alist[low]
while low < high:
#high 左移
while low < high and alist[high] >= mid:
high -= 1
alist[low] = alist[high]
#low 右移
while low < high and alist[low] < mid:
low += 1
alist[high] = alist[low]
alist[low] = mid
quick_sort(alist, first, low-1)
quick_sort(alist, low+1, last)
最優時間複雜度：o(nlogn)
最壞時間複雜度：o(nlogn)
穩定性：穩定
def merge_sort(alist):
"""歸併排序"""
n = len(alist)
if n == 1:
return alist
mid = n // 2
left_li = merge_sort(alist[:mid])
right_li = merge_sort(alist[mid:])
left_pointer, right_pointer = 0, 0
result =
while left_pointer if left_li[left_pointer] < right_li[right_pointer]:
left_pointer += 1
else:
right_pointer += 1
result += left_li[left_pointer:]
result += right_li[right_pointer:]
return result
python 實現常見排序演算法
coding utf 8 bubble sort 氣泡排序 時間複雜度最壞為o n2 最優的為n import time def bubble sort alist 氣泡排序 param alist return cur 1 while cur len alist 1 and len alist 1...
常見排序演算法 python實現
穩定性是指序列中相同的數字在排序後相對位置不發生改變 常見的且穩定的排序演算法有冒泡 歸併 插入，其餘的為非穩定的排序演算法 def bubble sort alist for j in range len alist 1 0,1 for i in range j if alist i alist ...
常見排序演算法的python實現
氣泡排序和選擇排序 defbubblesort alist for i in range len alist 1 0,1 for j in range i if alist j alist j 1 alist j alist j 1 alist j 1 alist j return alist al...