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# -*- coding:UTF-8 -*-

import functools

# Python3.x和Python2.x对于map、reduce、filter的处理变得不同

# Python3.x中map和filter的输出是一个map型和filter型, 需要从里面取出需要的值

# Python2.x中map和filter输出的直接是一个list

# Python3.x中使用reduce需要引入functools

# 使用map把list中的int变为str

map(str, [1, 2, 3, 4, 5, 6, 7, 8, 9])

# 使用map()把名字规范化, 首字母大写,其余小写

def standardName(s):

return s.capitalize()

print([x for x in map(standardName, ['adam', 'LISA', 'barT'])])

# 在Python2.x中应该使用print(map(standardName, ['adam', 'LISA', 'barT']))

# 使用reduce()输出一个list的所有数的乘积

def prod(aList):

return functools.reduce(lambda x, y: x*y, aList)

print(prod([1, 2, 3, 4, 5]))

# 使用filter()打印100以内的素数

def isPrime(n):

isPrimeFlag = True

if n <= 1:

isPrimeFlag = False

i = 2

while i * i <= n:

if n % i == 0:

isPrimeFlag = False

break

i += 1

return n if isPrimeFlag else None

print(filter(isPrime, range(101)))