python之道05
1.写代码，有如下列表，按照要求实现每一个功能
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
1)计算列表的长度并输出
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
print(len(li))
'''
输出结果
5
'''
2)列表中追加元素"seven", 并输出添加后的列表
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
li.append('seven')
print(li)
'''
输出结果
['alex', 'WuSir', 'ritian', 'barry', 'wenzhou', 'seven']
'''
3)请在列表的第1个位置插入元素"Tony", 并输出添加后的列表
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
li.insert(0,'Tony')
print(li)
'''
输出结果
['Tony', 'alex', 'WuSir', 'ritian', 'barry', 'wenzhou']
'''
4)请修改列表第2个位置的元素为"Kelly", 并输出修改后的列表
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
li[1] = 'Kelly'
print(li)
'''
输出结果
['alex', 'Kelly', 'ritian', 'barry', 'wenzhou']
'''
5)请将列表l2 = [1, "a", 3, 4, "heart"]的每一个元素添加到列表li中，一行代码实现，不允许循环添加。
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
l2 = [1, "a", 3, 4, "heart"]
li = li + l2
print(li)
'''
输出结果
['alex', 'WuSir', 'ritian', 'barry', 'wenzhou', 1, 'a', 3, 4, 'heart']
'''
6)请将字符串s = "qwert"的每一个元素添加到列表li中，一行代码实现，不允许循环添加。
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
s = "qwert"
li.extend(s)
print(li)
'''
输出结果
['alex', 'WuSir', 'ritian', 'barry', 'wenzhou', 'q', 'w', 'e', 'r', 't']
'''
7)请删除列表中的元素"ritian", 并输出输出后的列表
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
li.remove('ritian')
print(li)
'''
输出结果
['alex', 'WuSir', 'barry', 'wenzhou']
'''
8)请删除列表中的第2个元素，并输出删除的元素和删除元素后的列表
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
print(li.pop(1))
print(li)
'''
输出结果
['alex', 'ritian', 'barry', 'wenzhou']
'''
9)请删除列表中的第2至4个元素，并输出删除元素后的列表
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
del li[1:4]
print(li)
'''
输出结果
['alex', 'wenzhou']
'''
10)请将列表所有得元素反转，并输出反转后的列表
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
print(li[::-1])
'''
输出结果
['wenzhou', 'barry', 'ritian', 'WuSir', 'alex']
'''
# 方法二
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
li.reverse()
print(li)
'''
输出结果
['wenzhou', 'barry', 'ritian', 'WuSir', 'alex']
'''
11)请计算出"alex"元素在列表li中出现的次数，并输出该次数。
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzhou"]
print(li.count('alex'))
'''
输出结果
1
'''
2.写代码，有如下列表，利用切片实现每一个功能
1)通过对li列表的切片形成新的列表l1, l1 = [1, 3, 2]
答案:
li = [1, 3, 2, "a", 4, "b", 5, "c"]
l1 = li[:3]
print(l1)
'''
输出结果
[1, 3, 2]
'''
2)通过对li列表的切片形成新的列表l2, l2 = ["a", 4, "b"]
答案:
li = [1, 3, 2, "a", 4, "b", 5, "c"]
l2 = li[3:6]
print(l2)
'''
输出结果
['a', 4, 'b']
'''
3)通过对li列表的切片形成新的列表l3, l3 = ["1,2,4,5]
答案:
li = [1, 3, 2, "a", 4, "b", 5, "c"]
l3 = li[::2]
print(l3)
'''
输出结果
[1, 2, 4, 5]
'''
4)通过对li列表的切片形成新的列表l4, l4 = [3, "a", "b"]
答案:
li = [1, 3, 2, "a", 4, "b", 5, "c"]
l4 = li[1:-2:2]
print(l4)
'''
输出结果
[3, 'a', 'b']
'''
5)通过对li列表的切片形成新的列表l5, l5 = ["c"]
答案:
li = [1, 3, 2, "a", 4, "b", 5, "c"]
l5 = li[-1:]
print(l5)
'''
输出结果
c
'''
6)通过对li列表的切片形成新的列表l6, l6 = ["b", "a", 3]
答案:
li = [1, 3, 2, "a", 4, "b", 5, "c"]
l6 = li[-3::-2]
print(l6)
'''
输出结果
['b', 'a', 3]
'''
3.写代码，有如下列表，按照要求实现每一个功能。
1)将列表lis中的"tt"变成大写（用两种方式）
答案:
# 方式一:
lis = [2, 3, "k", ["qwe", 20, ["k1", ["tt", 3, "1"]], 89], "ab", "adv"]
print(lis[3][2][1][0].upper())
'''
输出结果
TT
'''
# 方式二
lis = [2, 3, "k", ["qwe", 20, ["k1", ["tt", 3, "1"]], 89], "ab", "adv"]
lis[3][2][1][0] = 'TT'
print(lis)
'''
输出结果
TT
'''
2)将列表中的数字3变成字符串"100"（用两种方式）
答案:
# 方式一
lis = [2, 3, "k", ["qwe", 20, ["k1", ["tt", 3, "1"]], 89], "ab", "adv"]
lis[1] = '100'
lis[3][2][1][1] = '100'
print(lis)
'''
输出结果
[2, '100', 'k', ['qwe', 20, ['k1', ['tt', '100', '1']], 89], 'ab', 'adv']
'''
# 方式二
lis = [2, 3, "k", ["qwe", 20, ["k1", ["tt", 3, "1"]], 89], "ab", "adv"]
lis[1] = str(lis[1] + 97)
lis[3][2][1][1] = str(lis[3][2][1][1] + 97)
print(lis)
'''
输出结果
[2, '100', 'k', ['qwe', 20, ['k1', ['tt', '100', '1']], 89], 'ab', 'adv']
'''
3)将列表中的字符串"1"变成数字101（用两种方式）
答案:
# 方式一:
lis = [2, 3, "k", ["qwe", 20, ["k1", ["tt", 3, "1"]], 89], "ab", "adv"]
lis[3][2][1][2] = 101
print(lis)
'''
输出结果
[2, 3, 'k', ['qwe', 20, ['k1', ['tt', 3, 101]], 89], 'ab', 'adv']
'''
# 方式二:
lis = [2, 3, "k", ["qwe", 20, ["k1", ["tt", 3, "1"]], 89], "ab", "adv"]
lis[3][2][1][2] = int(lis[3][2][1][2]) + 100
print(lis)
'''
输出结果
[2, 3, 'k', ['qwe', 20, ['k1', ['tt', 3, 101]], 89], 'ab', 'adv']
'''
4.请用代码实现
li = ["alex", "wusir", "taibai"]
利用下划线将列表的每一个元素拼接成字符串"alex_wusir_taibai"
答案:
li = ["alex", "wusir", "taibai"]
print(li[0]+'_'+li[1]+'_'+li[2])
'''
输出结果
alex_wusir_taibai
'''
5.利用for循环和range打印出下面列表的索引
li = ["alex", "WuSir", "ritian", "barry", "wenzho"]
答案:
# 方式一:for循环 (这个理解错了题意,请看方式二)
li = ["alex", "WuSir", "ritian", "barry", "wenzho"]
count = -1
for i in li:
count += 1
print(count)
'''
输出结果
0
1
2
3
4
'''
# 方式二:for和range
li = ["alex", "WuSir", "ritian", "barry", "wenzho"]
for i in range(len(li)):
print(i)
'''
输出结果
0
1
2
3
4
'''
6.利用while循环打印出下面列表的索引
li = ["alex", "WuSir", "ritian", "barry", "wenzho"]
答案:
li = ["alex", "WuSir", "ritian", "barry", "wenzho"]
count = 0
while count < len(li):
print(count)
count += 1
'''
输出结果
0
1
2
3
4
'''
7.利用for循环和range找出100以内所有的偶数并将这些偶数添加到一个新列表中。
答案:
l1 = []
for i in range(100):
if i % 2 == 0:
l1.append(i)
print(l1)
'''
输出结果
[0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98]
'''
8.利用for循环和range找出50以内能被3整除的数，并将这些数插入到一个新列表中。
答案:
l1 = []
for i in range(50):
if i % 3 == 0:
l1.append(i)
print(l1)
'''
输出结果
[0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48]
'''
9.利用for循环和range从100~1，倒序打印
答案:
li = []
for i in range(1,101):
li.append(i)
print(li[::-1])
'''
输出结果
[100, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 79, 78, 77, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1]
'''
# 方式二
li = []
for i in range(1,101,-1):
li.append(i)
print(li)
'''
输出结果
[100, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 79, 78, 77, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1]
'''
10.利用for循环和range打印100~10，倒序将所有的偶数添加到一个新列表中，然后在对列表的元素进行筛选，将能被4整除的数留下来。
答案:
li = []
l2 = []
for i in range(10,101):
if i % 2 == 0:
li.append(i)
for l in li:
if l % 4 == 0:
l2.append(l)
print(l2)
'''
输出结果
[12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92, 96, 100]
'''
# 一行实现,不满足题意
li = []
for i in range(10,101):
if i % 4 == 0:
li.append(i)
print(li)
'''
输出结果
[12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92, 96, 100]
'''
# 方式三
11.利用for循环和range，将1-30的数字依次添加到一个列表中，并循环这个列表，将能被3整除的数改成*。
答案:
li = []
for i in range(1,31):
li.append(i)
for l in range(len(li)):
if li[l] % 3 == 0:
li[l] = '*'
print(li)
'''
输出结果
[1, 2, '*', 4, 5, '*', 7, 8, '*', 10, 11, '*', 13, 14, '*', 16, 17, '*', 19, 20, '*', 22, 23, '*', 25, 26, '*', 28, 29, '*']
'''
12.查找列表li中的元素，移除每个元素的空格，并找出以"A"或者"a"开头，并以"c"结尾的所有元素，并添加到一个新列表中,最后循环打印这个新列表。
li = ["TaiBai ", "alexC", "AbC ", "egon", " riTiAn", "WuSir", " aqc"]
答案:
l1 = []
li = ["TaiBai ", "alexC", "AbC ", "egon", " riTiAn", "WuSir", " aqc"]
for i in li:
j = i.strip()
if j[0].upper() == 'A' and j[-1] == 'c':
l1.append(j)
print(l1)
'''
输出结果
['aqc']
'''
13.开发敏感词语过滤程序，提示用户输入评论内容，如果用户输入的内容中包含特殊的字符：
敏感词列表 li = ["苍老师", "东京热", "武藤兰", "波多野结衣"]
则将用户输入的内容中的敏感词汇替换成等长度的（苍老师就替换**），并添加到一个列表中；如果用户输入的内容没有敏感词汇，则直接添加到上述的列表中。
答案:
li = ["苍老师", "东京热", "武藤兰", "波多野结衣"]
l1 = []
while 1:
comment = input('请输出评论内容: ')
if comment in li:
l1.append('*' * len(comment))
else:
l1.append(comment)
print(l1)
'''
输出结果
请输出评论内容: 不上班
['老男孩', '郭德纲', '***', '***', '许三多', '不上班']
'''
# 以上这个有bug,如果输入: '苍老师你好',就无法转换成*
# 方式二
comment = input('请输出评论内容: ')
for i in comment:
if
14.有如下列表（选做题）
li = [1, 3, 4, "alex", [3, 7, 8, "BaoYuan"], 5, "RiTiAn"]
循环打印列表中的每个元素，遇到列表则再循环打印出它里面的元素。
我想要的结果是：
1
3
4
alex
3
7
8
baoyuan
5
ritian
答案:
# 方式一
li = [1, 3, 4, "alex", [3, 7, 8, "BaoYuan"], 5, "RiTiAn"]
for i in li:
if type(i) == list:
for j in i:
if type(j) == str:
print(j.lower())
else:
print(j)
elif type(i) == str:
print(i.lower())
else:
print(i)
# 方式二
li = [1, 3, 4, "alex", [3, 7, 8, "BaoYuan"], 5, "RiTiAn"]
for i in li:
if type(i) == int:
print(i)
elif type(i) == str:
if i.lower() == "ritian":
print(i.lower())
else:
print('"' + str(i).lower() + '"')
else:
for j in i:
if j == 7:
print(str(j) + ',')
elif type(j) == int:
print(j)
else:
print('"' + str(j).lower() + '"')
'''
输出结果
1
3
4
"alex"
3
7,
8
"baoyuan"
5
ritian
'''
端午作业:
1.day4之前所有内容,进行笔记整理
2.整理day4之前的所有的知识点画思维导图
3.继续向后预习
