day3-课堂代码

# a = ('哈哈', 'xixi', 'hehe')
# print(a[0])
# print(a[0:2])
#
# # 列表
# a = ['哈哈', 'xixi', 'hehe', 1, True, (1, 2, 3)]
# print(a[0])
# print(a[0:2])
# a[1] = '嘻嘻'  # 修改，列表：可变数据类型
# a[-1] = '呵呵'
# print(a)
# a.append('旺旺')  # 追加元素
# print(a)
# b = [1, 2, 3]
# a.append(b)
# print(a)
# a.extend(b)
# print(a)
# a += b
# print(a)
# a[1:1] = b
# print(a)
# a[1:] = [1, 2, 3]  # 分片赋值
# print(a)
# a[:] = [1, 2, 3]
# print(a)
# a[0:1] = []  # 删除
# print(a)
# del (a[0:1])  # 删除
# print(a)
#
# str1 = 'hello huice'
# a = list(str1)
# print(a)
# print(a.count('e'))
# print(a.index('l'))
# print(a.append('mm'))  # 打印函数，但a.append()没有返回值
# print(a)  # 打印操作的对象有返回值，说明a.append()做的是原地操作，改变对象本身
#
# a.pop()  # 弹出最后一个元素
# a.pop(1)
# print(a.pop(1))  # 既有返回值，又修改了对象
# print(a)
# a.remove('h')  # 没有返回值，pop可以不传参数，传的是索引，remove传的是元素
# print(a)
#
# a.reverse()  # 没有返回值，原地反向
# print(a)

a = ['Java', 'python', 'C', 'Ruby', 'PHP', 'JS']

# a.sort()
# print(a)
# a.sort(reverse=True)
# print(a)
# a.sort(reverse=True, key=len)
# print(a)

# def my_sort(a):
#     #return len(a)
#     return a[-1]
#
# a.sort(key=my_sort)
# print(a)

# 匿名函数
# a.sort(key=lambda a: a[-1])
# print(a)
#
# table = [(1, 'zhangsan', 3000), (2, 'lisi', 2500), (3, 'tiantian', 20000)]
#
# table.sort(reverse=True, key=lambda a: a[-1])
# print(table)
#
# # sort原地排序，sorted有返回值，原来列表不变
# table = [(1, 'zhangsan', 3000), (2, 'lisi', 2500), (3, 'tiantian', 20000)]
# print(sorted(table, key=lambda x: x[-1], reverse=True)[0][1])
# print(table)

# 遍历列表
# a = ['Java', 'python', 'C', 'Ruby', 'PHP', 'JS']
# for ele in a:
#     print('*')
#
# for i in range(len(a)):  # '0,'省略
#     print(a[i])
#
# for i, j in enumerate(a):
#     print(i, j)
#
# a = [1, 2, 3, 4, 5]
# print([ele ** 2 for ele in a])

# a = [1, 2, 3]
# b = [2, 3, 4]
# print(a + b)
# print(a * 3)

# a = [1, 2, 3]
# b = ['zhangsan', 'lisi', 'tiantian']
# c = ['2000', '3000', '20000']
# print(tuple(zip(a, b, c)))
# for i in zip(a, b, c):
#     print(i)

# str0 = 'xiaoming&xiaohua'
# print(str0.split('i'))
# print(''.join(str0))

# eval使用的前提是，这个字符串长的像列表或元祖
# str = '[1,"a",23]'
# print(type(eval(str)))
#
# str = '(1,"a",3)'
# print(type(eval(str)))

# Set集合 无序不重复元素集 不支持索引 只能用for in 循环，不能用 for in range
# s1 = {1, 5, 2, 3, 5, 2}  # 集合
# d1 = {'name': 'zhangsan', 'age': '18'}  # 字典 key value
# print(type(s1))
# print(type(d1))
# print(s1)
#
# for i in s1:
#     print(i)
#
# s1 = [8, 1, 5, 2, 3, 5, 2]
# print(list(set(s1)))  # 用来给列表去重
# lst0 = list(set(s1))
# lst0.sort(key=lambda x: s1.index(x))
# print(lst0)
#
# new = []
# for ele in s1:
#     if ele not in new:
#         new.append(ele)
# print(new)

# 字典 {k1:v2,k2:v2}
a = {'zhangsan': {'语文': '90', '数学': '100'}, 'lisi': {'语文': '90', '数学': '100'}}

dic = {'name': 'zhangsan', 'age': '17'}
print(dic['age'])
dic['age'] = 18  # 修改
print(dic)

print(dic.get('name'))
print(dic['name'])

# print(dic.get('six')) #当取不到时会报错返回None
# print(dic['six'])     #当取不到时会报错

dic['six'] = '女'  # 赋值
print(dic)

# dic{}
# dic[key]=value

# dic = {}
# str = 'k1:1|k2:2|k3:3'
# str = str.split('|')
# for i in str:
#     i = i.split(':')
#     n = i[0]
#     m = i[1]
#     dic[n] = int(m)
# print(dic)

# dic = {}
# str = 'k1:1|k2:2|k3:3'
# str = str.split('|')
# for i in str:
#     key = i.split(':')[0]
#     value = i.split(':')[-1]
#     dic[key] = int(value)
# print(dic)
#
# print('k1' in dic)
# print(dic.keys())
# print(dic.values())
# print(dic.items())
#
# dic.pop('k1')
# print(dic)
#
# # dic = {}
# # a = ['name', 'age', 'six']
# # print(dic.fromkeys(a))
#
# a = {'k2': 10, 'k4': 5}
# dic.update(a)
# print(dic)

# 字典的遍历
dic = {'k1': 1, 'k2': 2}
for key in dic.keys():
    print(key)
for value in dic.values():
    print(value)
for item in dic.items():
    print(item)
for k, v in dic.items():
    print(k, v)

# k1:1|k2:2|k3:3
#
# dic ={'k3': 3, 'k2': 2, 'k1': 1}

print(sorted(dic.keys(), reverse=True))
print(sorted(dic.values(), reverse=True))
print(sorted(dic.items(), reverse=True))

s = {'zhagnsan': 98, 'lily': 99}
print(sorted(s.items(), key=lambda x: x[-1], reverse=True))

# 函数
def add_two_number(x, y):  # x、y形式参数 形参
    '求加法的函数'
    return x + y

a = 3
b = 4
# add_two_number(a, b)  # a、b 实际参数 实参
# add_two_number(3, 4)  # 3、4 实际参数 实参
print(add_two_number.__doc__)
print(add_two_number(y=4, x=3))