插入和冒泡排序部分工作

Question

我是 Python 的數據結構和算法的新手。 我在我的庫存程序中實施了插入和冒泡排序。 當我對當前字典進行排序時，我的插入排序和冒泡排序都有效。 但是，在添加新項目或從我的字典中刪除項目后，我的插入和冒泡排序出現了關鍵錯誤。 我試過將字典更改為 [{description..}] 並將 market[len(market) + 1] 更改為 market[len(market)] 。 這些都不起作用。 如果有人幫助我編輯我的代碼或向我解釋發生了什么，我將不勝感激。 先感謝您：”）

market = {0: {'Description': 'Chocolate', 'Stock': 65, 'Price': 3.2, 'Expiry': '27 Dec', 'Discount': 'eligible'},
          1: {'Description': 'Bread', 'Stock': 20, 'Price': 2.7, 'Expiry': '15 June', 'Discount': 'eligible'},
          2: {'Description': 'Apples', 'Stock': 97, 'Price': 10.6, 'Expiry': '12 July', 'Discount': 'not eligible'},
          3: {'Description': 'Potato', 'Stock': 81, 'Price': 20.8, 'Expiry': '13 April', 'Discount': 'not eligible'},
          4: {'Description': 'Ice', 'Stock': 91, 'Price': 9.8, 'Expiry': '16 April', 'Discount': 'not eligible'}
          }


def menu():
    print('Press 1: To Add items. ')
    print('Press 2: To View items. ')
    print('Press 3: To Remove items. ')
    print('Press 4: Use Insertion Sort. ')
    print('Press 5: Use Bubble Sort. ')
    print('Press 6: Use Binary Search. ')
    print('Press 7: View Total and Average stock level. ')
    print('Press q: To Quit program. ')
    return input('What would you like to do? ')


# print(len(market) + 1) # check counter


# Insertion Sort

def insertionSort(theSeq, key):

    for i in range(1, len(theSeq)):
        temp = theSeq[i][key]
        j = i
        while j > 0 and temp < theSeq[j - 1][key]:
               theSeq[j][key] = theSeq[j - 1][key]
               j = j - 1
        theSeq[j][key] = temp
    return theSeq


# Sorting Menu
def sort_menu(second_list, sort_type):
    print('1. Sort by Description')
    print('2. Sort by Price')

    # Get user input
    user_input = input('Please enter choice: ')

    if user_input == '1':
        second_list = sort_type(second_list, 'Description')
        print('Success! Inventory list is sorted by Description!')

    elif user_input == '2':
        second_list = sort_type(second_list, 'Price')
        print('Success! Inventory list is sorted by Price!')
    else:
        print('You have entered an invalid option!')

    # Return updated list
    return second_list


# Bubble Sort
def bubble_sort(second_list, key):

    # Create temp copy of list
    temp = second_list.copy()

    # Obtain length of list
    y = len(temp)

    for i in range(y - 1, 0, -1):
        for j in range(i):
            if temp[j][key] > temp[j + 1][key]:
                temp[j], temp[j + 1] = temp[j + 1], temp[j]
    # Return updated list
    return temp

# Binary Search
def binarysearch(dictionary,item):
    global founditem
    itemlist = []
    for item2 in dictionary:
        itemlist.append(item2)
    first = 0
    last = len(itemlist) - 1
    found = False

    while first <= last and not found:
        midpoint = (first + last)//2
        if itemlist[midpoint] == item:
            # print(midpoint) test print out
            founditem = dictionary.get(midpoint)
            found = True
        else:
            if item < itemlist[midpoint]:
                last = midpoint-1
            else:
                first = midpoint+1
    return founditem


# Print total and average stock level
def average(market):
    n = len(market)
    total = 0
    for i in range(0,n):
        total += market[i]["Stock"]
    average = total/n
    return average

def total(market):
    n = len(market)
    total = 0
    for i in range(0,n):
        total += market[i]["Stock"]
    return total


while True:
    run = menu()
    if run == '1':
        # market[len(market) + 1] = {}
        # addMarket = input('Item to be added to Market? ')
        # market[len(market) + 1]['Description'] = addMarket
        name = input('Item to be added to Market? ')
        price = float(input('Price of food?'))
        amount = int(input('Qty of food to be added to stock? '))
        expiry = input('Enter expiry date: ')
        discount = input('Enter eligibility of discount: ')
        market[len(market) + 1] = {'Description': name, 'Stock': amount, 'Price': price, 'Expiry': expiry,
                                   'Discount': discount}

    elif run == '2':
        for i in market:
            item = market[i]
            print("Item No - %d Description - %s Stock - %d Price - %.2f Expiry - %s Discount - %s" % (
            i, item['Description'], item['Stock'], item['Price'], item['Expiry'], item['Discount']))


    elif run == '3':
        remove = int(input('Key in item number to remove: '))
        del market[remove]

    elif run == '4':
        market = sort_menu(market, insertionSort)

    elif run == '5':
        market = sort_menu(market, bubble_sort)
    #
    elif run == '6':
        key = int(input('Enter key you want to search: '))
        print(binarysearch(market, key))

    elif run == '7':
        print('')
        print('Total stock level is',total(market), 'and Average stock level is', average(market))
        print('')

    else:
        quit = str()
        while quit.upper() != "Q":
            quit = input("Enter Q or q to return to Main Menu. ")
            if quit.upper() == "Q":
                print('Thank you for using MamaStore!')
                menu()

Answer 1

插入代碼的問題是您通過每次插入跳過一個索引來插入新元素。 市場的初始大小為 5，因此當您插入新元素時，該元素應在索引 5 處為 go（起始索引為 0），但 market[len(market)+1] 在索引 6 處插入。因此，當您在排序中運行順序循環時它會拋出一個鍵錯誤，因為你沒有 5 作為鍵。
同樣在刪除時，當您刪除任何項目時，序列中斷會導致鍵錯誤，就像在插入的情況下一樣。 您可能應該考慮在字典的鍵上運行循環，在您的情況下是那些項目 ID。
但是，對於您的代碼，將 dict 轉換為列表然后稍后在返回之前執行排序將很方便將其轉換回字典。 我在下面附上了一個工作代碼：

market = {0: {'Description': 'Chocolate', 'Stock': 65, 'Price': 3.2, 'Expiry': '27 Dec', 'Discount': 'eligible'},
          1: {'Description': 'Bread', 'Stock': 20, 'Price': 2.7, 'Expiry': '15 June', 'Discount': 'eligible'},
          2: {'Description': 'Apples', 'Stock': 97, 'Price': 10.6, 'Expiry': '12 July', 'Discount': 'not eligible'},
          3: {'Description': 'Potato', 'Stock': 81, 'Price': 20.8, 'Expiry': '13 April', 'Discount': 'not eligible'},
          4: {'Description': 'Ice', 'Stock': 91, 'Price': 9.8, 'Expiry': '16 April', 'Discount': 'not eligible'}
          }


def menu():
    print('Press 1: To Add items. ')
    print('Press 2: To View items. ')
    print('Press 3: To Remove items. ')
    print('Press 4: Use Insertion Sort. ')
    print('Press 5: Use Bubble Sort. ')
    print('Press 6: Use Binary Search. ')
    print('Press 7: View Total and Average stock level. ')
    print('Press q: To Quit program. ')
    return input('What would you like to do? ')


# Insertion Sort

def insertionSort(theSeq, key):
    temp1 = [i for i in theSeq.values()]
    for i in range(0, len(temp1)):
        temp = temp1[i][key]
        j = i
        while j > 0 and temp < temp1[j - 1][key]:
            temp1[j][key] = temp1[j - 1][key]
            j = j - 1
        temp1[j][key] = temp
    s = {}
    for i in range(len(temp1)):
        s[i] = temp1[i]
    return s


# Sorting Menu
def sort_menu(second_list, sort_type):
    print('1. Sort by Description')
    print('2. Sort by Price')

    # Get user input
    user_input = input('Please enter choice: ')
    if user_input == '1':
        second_list = sort_type(second_list, 'Description')
        print('Success! Inventory list is sorted by Description!')

    elif user_input == '2':
        second_list = sort_type(second_list, 'Price')
        print('Success! Inventory list is sorted by Price!')
    else:
        print('You have entered an invalid option!')

    # Return updated list
    return second_list


# Bubble Sort
def bubble_sort(second_list, key):
    # Create temp copy of list
    temp = [i for  i in second_list.values()]

    # Obtain length of list
    y = len(temp)

    for i in range(y - 1, 0, -1):
        for j in range(i):
            if temp[j][key] > temp[j + 1][key]:
                temp[j], temp[j + 1] = temp[j + 1], temp[j]
    # Return updated list
    s = {}
    for i in range(len(temp)):
        s[i] = temp[i]
    return s

# Binary Search
def binarysearch(dictionary,item):
    global founditem
    itemlist = []
    for item2 in dictionary:
        itemlist.append(item2)
    first = 0
    last = len(itemlist) - 1
    found = False

    while first <= last and not found:
        midpoint = (first + last)//2
        if itemlist[midpoint] == item:
            # print(midpoint) test print out
            founditem = dictionary.get(midpoint)
            found = True
        else:
            if item < itemlist[midpoint]:
                last = midpoint-1
            else:
                first = midpoint+1
    return founditem


# Print total and average stock level
def average(market):
    n = len(market)
    total = 0
    for i in range(0,n):
        total += market[i]["Stock"]
    average = total/n
    return average

def total(market):
    n = len(market)
    total = 0
    for i in range(0,n):
        total += market[i]["Stock"]
    return total


while True:
    run = menu()
    if run == '1':
        name = input('Item to be added to Market? ')
        price = float(input('Price of food?'))
        amount = int(input('Qty of food to be added to stock? '))
        expiry = input('Enter expiry date: ')
        discount = input('Enter eligibility of discount: ')
        market[len(market)] = {'Description': name, 'Stock': amount, 'Price': price, 'Expiry': expiry,
                                   'Discount': discount}

    elif run == '2':
        for i in market:
            item = market[i]
            print("Item No - %d Description - %s Stock - %d Price - %.2f Expiry - %s Discount - %s" % (
            i, item['Description'], item['Stock'], item['Price'], item['Expiry'], item['Discount']))

    elif run == '3':
        remove = int(input('Key in item number to remove: '))
        del market[remove]

    elif run == '4':
        market = sort_menu(market, insertionSort)

    elif run == '5':
        market = sort_menu(market, bubble_sort)

    elif run == '6':
        key = int(input('Enter key you want to search: '))
        print(binarysearch(market, key))

    elif run == '7':
        print('')
        print('Total stock level is',total(market), 'and Average stock level is', average(market))
        print('')

    else:
        quit = str()
        while quit.upper() != "Q":
            quit = input("Enter Q or q to return to Main Menu. ")
            if quit.upper() == "Q":
                print('Thank you for using MamaStore!')
                menu()

希望能幫助到你！

Answer 2

您正在混合鍵和索引的概念。 當你添加一個項目時，你給它鍵 len(market) + 1 即 5 + 1。因此鍵 '5' 未被使用，你得到一個鍵為 1, 2, 3, 4, 6 的字典

下一次，當您開始排序時，您嘗試使用這些鍵作為索引。 使用range(y - 1, 0, -1) ，您迭代一組連續的整數，因此在 key='5' 上出現鍵錯誤。 您應該遍歷鍵。 要獲取字典的索引，請使用例如類似

for i, d in enumerate(market):...

刪除項目時會出現同樣的問題。 鍵被刪除，留下一個字典，例如鍵：0、1、2、4。你現在在 key='3' 上得到一個鍵錯誤

希望這能提供足夠的線索來更正您的腳本。