Python编程之数据结构与算法练习_004

Some排序算法的Python实现。不废话写原理，直接撸代码。

1.Bubble sort 冒泡排序

import random
import copy

maxSize = 10000
maxValue = 10000

#Generate random data
array=[0]*maxSize
for i in range(maxSize):
    array[i] = random.randint(10,maxValue)
    
#Correct method
originalArray = copy.deepcopy(array)
testArray = copy.deepcopy(array)
testArray.sort()

#Bubble sort
swaped = False
for i in range(maxSize):
    swaped = False
    for j in range(0, maxSize - i - 1):
        if array[j] > array[j+1]:
            array[j], array[j+1] = array[j+1], array[j]
            swaped = True
    if not swaped:
        break
#Compare
for i in range(maxSize):
    if testArray[i] != array[i]:
        print("Fucked.")
        print(originalArray)
        break
else:
    print("Success.")

2.Insertion sort 插入排序

#插入排序
import random
import copy

maxSize = 10000
maxValue = 10000

#Generate random data
array=[0]*maxSize
for i in range(maxSize):
    array[i] = random.randint(10,maxValue)
#Correct method
testArray = copy.deepcopy(array)
testArray.sort()

#Insertion sort
for i in range(1, maxSize):
    for j in range(i, 0, -1):
        if array[j] <= array[j-1]:
            array[j],array[j-1] = array[j-1],array[j]
        else:
            break
#Compare
for i in range(maxSize):
    if testArray[i] != array[i]:
        print("Fucked.")
        print("Fucked sample:{}".format(lst))
        break
else:
    print("Success.")

3.Quick sort 快速排序

def Partition(lst, left,right):
    
    partValue = lst[right]
    leftIndex = left - 1
    curIndex = left
    rightIndex = right
    
    while curIndex < rightIndex:
        if lst[curIndex] < partValue :
            leftIndex += 1        
            lst[curIndex], lst[leftIndex] = lst[leftIndex], lst[curIndex]
            curIndex += 1
        elif lst[curIndex] > partValue:
            rightIndex -= 1
            lst[curIndex], lst[rightIndex] = lst[rightIndex], lst[curIndex]
        else:
            curIndex += 1
    else:
        lst[rightIndex], lst[right] = lst[right], lst[rightIndex] #将用来划分的值交换至最终位置
        return [leftIndex ,rightIndex+1 ]
    
def QuickSort(lst, left, right):
    if left < right :
        lstTmp = Partition(lst,left,right)
        QuickSort(lst, left, lstTmp[0])
        QuickSort(lst, lstTmp[1], right)
        
# Test
def Compare(lstX, lstY):
    for i in range(len(lstX)):
        if lstX[i] != lstY[i]:
            return False
    else:
        return True
    
maxRound = 10000
maxValue = 1000
arrLength = 10000
for i in range(maxRound):
    lst = [random.randint(-maxValue,maxValue) for i in range(arrLength)]
　　 lstCopy = copy.deepcopy(lst)
    QuickSort(lst, 0, len(lst) - 1)
    correctResult = sorted(lstCopy)
    if not Compare(correctResult, lst):
        print("Fucked.")
        print("Fucked sample:{}".format(lst))
        break
else:
    print("Success.")

4.Merge sort 归并排序

#归并排序

import random

def merge(lst, left, middle, right):
    
    leftIndex = left
    rightIndex = middle+1
    lstHelp = []
    
    while leftIndex <= middle and rightIndex <= right:
        if lst[leftIndex] <= lst[rightIndex]:
            lstHelp.append(lst[leftIndex])
            leftIndex += 1
        else:
            lstHelp.append(lst[rightIndex])
            rightIndex += 1
    
    while leftIndex <= middle:
        lstHelp.append(lst[leftIndex])
        leftIndex += 1
    
    while rightIndex <= right:
        lstHelp.append(lst[rightIndex])
        rightIndex += 1
    
    for i in range(len(lstHelp)):
        lst[left+i] = lstHelp[i]
        
def MergeSort(lst, left, right):
    
    if left == right:
        return
    
    middle = left + ((right - left)>>1)
    MergeSort(lst, left, middle,)
    MergeSort(lst, middle+1, right)
    merge(lst, left, middle, right)
    
    
# Test
def Compare(lstX, lstY):
    for i in range(len(lstX)):
        if lstX[i] != lstY[i]:
            return False
    else:
        return True
    
maxRound = 10000
maxValue = 1000
arrLength = 1000
for i in range(maxRound):
    lst = [random.randint(-maxValue,maxValue) for _ in range(arrLength)]
　　 lstCopy = copy.deepcopy(lst)
    MergeSort(lst, 0, len(lst) - 1)
    correctResult = sorted(lstCopy)
    if not Compare(correctResult, lst):
        print("Fucked.")
        print("Fucked sample:{}".format(lst))
        break
else:
    print("Success.")