Python列表练习题

1、创建一个空列表，命名为names，往里面添加 Lihua、Rain、Jack、Xiuxiu、Peiqi和Black元素。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]

2、往(1)中的names列表里Black前面插入一个Blue。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")

3、把names列表中Xiuxiu的名字改成中文。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
names[names.index("Xiuxiu")] = "秀秀"

4、往names列表中Rain后面插入一个子列表["oldboy","oldgirl"]。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
names[names.index("Xiuxiu")] = "秀秀"
names.insert(2,["oldboy","oldgirl"])
print(names) # 验证

5、返回names列表中Peiqi的索引值（下标）。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
names[names.index("Xiuxiu")] = "秀秀"
names.insert(2,["oldboy","oldgirl"])
print(names.index("Peiqi"))

6、创建新列表[1,2,3,4,2,5,6,2,]，合并到names列表中。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
names[names.index("Xiuxiu")] = "秀秀"
names.insert(2,["oldboy","oldgirl"])
print(names.index("Peiqi"))

numbers = [1,2,3,4,2,5,6,2]
names.extend(numbers)  # extend()方法表示合并
print(names)

7、取出names列表中索引4-7的元素。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
names[names.index("Xiuxiu")] = "秀秀"
names.insert(2,["oldboy","oldgirl"])
print(names.index("Peiqi"))

numbers = [1,2,3,4,2,5,6,2]
names.extend(numbers)  # extend()方法表示合并
print(names)

print(names[4:8])

8、取出names列表中索引2-10的元素，步长为2。

#! -*-coding:utf-8 -*-
names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
# print(names)
names[names.index("Xiuxiu")] = "秀秀"
# print(names)
names.insert(2,["oldboy","oldgirl"])
# print(names)
print(names.index("Peiqi"))

numbers = [1,2,3,4,2,5,6,2]
names.extend(numbers)
print(names)

print(names[2:11:2]) # 列表切片“顾头不顾尾”，步长表示在指定范围间隔取值

9、取出names列表中最后3个元素。

#! -*-coding:utf-8 -*-
names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
# print(names)
names[names.index("Xiuxiu")] = "秀秀"
# print(names)
names.insert(2,["oldboy","oldgirl"])
# print(names)
print(names.index("Peiqi"))

numbers = [1,2,3,4,2,5,6,2]
names.extend(numbers)
print(names)

print(names[-3:]) # [-3:]表示取值范围为从列表的倒数第三个到末尾

10、循环names列表，打印每个元素的索引值和元素。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
names[names.index("Xiouxiu")] = "秀秀"
names.insert(2,["oldboy","oldgirl"])
print(names.index("Peiqi"))

numbers = [1,2,3,4,2,5,6,2]
names.extend(numbers)
print(names) # 验证

#方法1
for i in names:
    print(names.index(i),i)  
# 方法2 enumerate()枚举 
for index,i in enumerate(names):
    print(index,i) 

11、循环names列表，打印每个元素的索引值和元素，当索引值为偶数时，把对应的元素改成-1。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
names[names.index("Xiuxiu")] = "秀秀"
names.insert(2,["oldboy","oldgirl"])
print(names.index("Peiqi"))

numbers = [1,2,3,4,2,5,6,2]
names.extend(numbers)
print(names) # 验证

for index,i in enumerate(names):
    if index%2==0:
        names[index] = -1
        print(index,i)
print(names)

12、names列表里有3个2，请返回第二个2的索引值，不要人肉，要动态找。

#！-*- coding:utf-8 -*-

names = ["Lihua","Rain","Jack","Xiuxiu","Peiqi","Black"]
names.insert(-1,"Blue")
names[names.index("Xiuxiu")] = "秀秀"
names.insert(2,["oldboy","oldgirl"])
print(names.index("Peiqi"))

numbers = [1,2,3,4,2,5,6,2]
names.extend(numbers)
print(names) # 验证

# 方法1 循环
count = 0
for index,i in enumerate(names):
    # print(index,i)
    if i == 2:
        count += 1
        while count == 2:
            print(index)
            break
    else:
        continue
# 方法2 
print(names.index(2,names.index(2)+1)) 

13、现有商品列表如下：

　　products =   [["iphone",6888],["MacPro",14800],["小米6",2499],["Coffee",31],["Book",60],["Nike",699]]，需打印出以下格式：

------  商品列表 ------
0  iphone    6888
1  MacPro    14800
2  小米6        2499
3  Coffee      31
4  Book        60
5  Nike         699

　　参考答案如下：

#！-*- coding:utf-8 -*-

products = [["iphone",6888],["MacPro",14800],["小米6",2499],["Coffee",31],["Book",60],["Nike",699]]
print("--------- 商品列表 --------")
for index,i in enumerate(products):
    print("%s  %s    %s"%(index,i[0],i[1]))

14、根据（13）里的products列表写一个循环，不断询问用户想买什么，用户选择一个商品编号，就把对应的商品添加到购物车里，最终用户输入q退出时，打印购买的商品列表。

　　参考答案如下：

#!-*- coding:utf-8 -*-
products = [["iphone",6888],["MacPro",14800],["小米6",2499],["Coffee",31],["Book",60],["Nike",699]]
shop_car = [] # 用户购物车
shop_cost = 0 # 用户花费的金额
exit_log = False # 标志位，默认设为False,退出
while not exit_log:
    print("------ 商品列表 ------")
    for index,i in enumerate(products):
        print("%s   %s  %s"%(index,i[0],i[1])) 
    user_choice = input("\n输入你想购买的产品序号(按“q”退出):")
    if user_choice.isdigit(): 
        # 判断用户输入的是否是数字
        user_choice = int(user_choice)  #强制转换为数字
        if user_choice>=0 and user_choice < len(products):
            # 判断用户购买的商品是否在商品列表中
            shop_car.append(products[user_choice]) # 加入购物车
            shop_cost += products[user_choice][1]  # 计算费用
            print("\n %s 已经加入你的购物车\n"%products[user_choice])
        else:
            print("抱歉，此商品不存在\n")
    elif user_choice == "q":
      # 用户选择退出
        if len(shop_car)>0:
            # 判断用户是否购买了商品
            print("\n------ 你的购物车 ------")
            for index,i in enumerate(shop_car):
                # index和i为临时变量，与前一个for循环里index和i作用的列表不同，故可重用
                print("%s  %s"%(i[0],i[1]))
            print("\n你此次购物的花费合计是:%s元\n"%shop_cost)
            exit_log = True # 退出购物
        else:
            exit_log = True # 未购买商品，不打印购物车商品，直接退出
    else:
        # 输入不合法
        exit_log = True