廖雪峰python3 返回函数 && 匿名函数练习题

# 利用闭包返回一个计数器函数，每次调用它返回递增整数：
'''
def createCounter():
    x = int(0)
    def counter():
        nonlocal x
        x += 1
        return x
    return counter
counterA = createCounter()
print(counterA(), counterA(), counterA(), counterA(), counterA()) # 1 2 3 4 5
counterB = createCounter()
if [counterB(), counterB(), counterB(), counterB()] == [1, 2, 3, 4]:
    print('测试通过!')
else:
    print('测试失败!')
'''
# 请用匿名函数改造下面的代码：
# def is_odd(n):
#     return n % 2 == 1
# L = list(filter(is_odd, range(1, 20)))
'''
L = list(filter(lambda x: x%2 == 1, range(1, 20)))
'''