from functools import reduce

from collections.abc import Iterator

def f(x):

return x * x

r = map(str, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13])

print(list(r))

def add(x, y):

return x + y

print(reduce(add, [1, 3, 5, 7, 9]))

def fn(x, y):

return x * 10 + y

print(reduce(fn, [1, 3, 5, 7, 9]))

def normalize(name):

return name[0].upper() + name[1:].lower()

L1 = ['adam', 'LISA', 'barT']

L2 = list(map(normalize, L1))

print(L2)

def prod(L):

def fn(x, y):

return x * y

return reduce(fn, L)

print('3 * 5 * 7 * 9 =', prod([3, 5, 7, 9]))

if prod([3, 5, 7, 9]) == 945:

print('测试成功!')

else:

print('测试失败!')

# 利用map和reduce编写一个str2float函数，把字符串'123.456'转换成浮点数123.456：

def str2float(s):

n = s.find('.')

print('n', n)

num_dict = {

'0': 0,

'1': 1,

'2': 2,

'3': 3,

'4': 4,

'5': 5,

'6': 6,

'7': 7,

'8': 8,

'9': 9

}

def char2int(s):

return num_dict[s]

def add(x, y):

return (x * 10 + y)

strInt = map(char2int, s.replace('.', ''))

return reduce(add, strInt) / (10**n)

print('str2float(\'123.456\') =', str2float('123.456'))

if abs(str2float('123.456') - 123.456) < 0.00001:

print('测试成功!')

else:

print('测试失败!')