## 3.1推导式练习 给定一个包含5个英语单词的列表，请构造1个字典以列表的元素为键，以每个键对应的单词字母个数为值。 ~~~ en_list = ["apple", "banana", "peach", "pineapple", "watermelon"] ~~~ ~~~ en_dict = {word: len(word) for word in en_list} en_dict ~~~ ## 3.4 练习:for循环和控制台打印 ``` # 假设有三名学生 students = ["小明", "小红", "小刚"] # 每位学生的分数 scores = [90, 85, 78] # 开始打印报告卡 print("学生分数报告卡：") # 对于每一个学生，进行一次循环 for i in range(len(students)): # 获取学生的名字和分数 student_name = students[i] score = scores[i] # 打印学生的名字和分数 print(f"{student_name}的分数是：{score}分") # 结束打印报告卡 print("报告卡打印完毕！") ``` ## 3.6 列表练习：计算销售额 ``` # 假设每天售出的商品和数量如下 sales = [ {"product": "苹果", "quantity": 10, "price": 5}, {"product": "香蕉", "quantity": 8, "price": 3}, {"product": "橙子", "quantity": 12, "price": 4}, ] # 计算总销售额 total_sales = 0 # 对于每一天的销售记录，进行一次循环 for sale in sales: # 获取商品的数量和价格 quantity = sale["quantity"] price = sale["price"] # 计算当天的销售额 daily_sales = quantity * price # 累加到总销售额 total_sales += daily_sales # 打印当天的销售额 print(f"{sale['product']}的销售额是：{daily_sales}元") # 打印总销售额 print("总销售额是：", total_sales, "元") ``` ## 3.7 列表的切片的练习 ``` # 食材列表 food_list = ["葱", "姜", "蒜", "料酒", "猪肝", "大闸蟹", "鸡丁", "花生米", "酱油", "淀粉"] # 获取所需食材 selected_food1 = food_list[0:4] selected_food2 = food_list[-4:] select_list = selected_food1+selected_food2 # 打印选中的食材 print("您选中的食材是：") for food in select_list: print(food) ``` ## 3.8列表组成字典 ``` list_food=["腰子","辣子","和牛","大闸蟹","黑虎虾","西兰花"] list_price=[68,0.5,128,60,40,12] list = {} for food,price in zip(list_food,list_price): list[food] = price list ``` ## 3.8 zip函数练习 ``` # 步骤 1: 创建一个包含客人名字和喜好的字典 guests = [ "老王", "老马", "老陈", "李小宝", "小林" ] likes=[ "川菜", "西式快餐", "南通菜", "东北菜", "法餐" ] feeds = [ "钵钵鸡", "巨无霸汉堡", "南通头菜", "锅包肉", "红酒鹅肝" ] # 步骤 3: 使用 zip 函数将客人和他们的喜好配对，并打印出来 preferences = list(zip(guests, likes)) print("客人的喜好:") for guest, preference in preferences: print(f"{guest} 喜欢 {preference}") # 步骤 4: 使用 zip 函数将客人和菜品配对，并创建一个新的字典 feeds_for_guests = list(zip(guests, gifts)) # 步骤 5: 打印新的字典，查看每个客人将收到的礼物 print("\n客人点的菜:") for guest, feeds in feeds_for_guests: print(f"{guest} 点了 {feeds}") ``` ## 3.8 字典——练习 ``` # 创建一个空的菜单字典 menu = { "宫保鸡丁": 35.0, "麻婆豆腐": 28.0, "清蒸鱼": 45.0, "炒时蔬": 20.0, "米饭": 5.0 } # 创建一个空的订单字典 order = {} def add_to_order(dish_name): """将菜品添加到订单中""" if dish_name in menu: if dish_name in order: order[dish_name] += 1 else: order[dish_name] = 1 else: print("该菜品不在菜单中。") def remove_from_order(dish_name): """从订单中删除菜品""" if dish_name in order: if order[dish_name] > 1: order[dish_name] -= 1 else: del order[dish_name] else: print("订单中不存在该菜品。") def calculate_total(): """计算订单的总价""" total = sum(menu[dish] * quantity for dish, quantity in order.items()) return total def view_order(): """查看订单详情""" if order: print("订单详情：") for dish, quantity in order.items(): print(f"{dish}: {quantity} 份") print(f"总价: {calculate_total()} 元") else: print("订单为空。") # 示例使用 add_to_order("宫保鸡丁") add_to_order("清蒸鱼") add_to_order("炒时蔬") view_order() remove_from_order("清蒸鱼") view_order() print(f"最终订单总价: {calculate_total()} 元") ``` ## 3.9 集合的练习 ``` # 你的购物清单 your_list = {"烤鸭", "篮球鞋", "iphone15", "牛肉卷", "提拉米苏"} # 朋友的购物清单 friend_list = {"烤鸭", "牛奶", "鸡蛋", "牛肉卷"} # 使用并集操作合并清单 combined_list = your_list.union(friend_list) print("合并后的购物清单：", combined_list) # 使用交集操作找出共同想购买的物品 common_items = your_list.intersection(friend_list) print("共同想购买的物品：", common_items) ``` ## 项目2