匿名函数的关键字为lambda,冒号前面是形参 冒号后面是返回值
from functools import reduce
def add(x,y):
return x + y
print(reduce(lambda x,y:x+y,[1,2,3,4,5])) //连加1+2+3+4+5
结果:15
#求元素的平方
print(list(map(lambda x:x ** 2,range(5))))
结果:[1,4,9,16,25]
#求10的阶乘
print(reduce(lambda x,y:x*y,range(1,11)))
结果:3628800
#匿名函数的默认参数
f = lambda x,y=2:x**y
print(f(3))
结果:9
print(f(2,4))
结果:16
#匿名函数的可变参数:
f = lambda *args:sum(args)
print(f(1,2,3,45,6))
结果:57
#匿名函数的关键字参数:
f = lambda **kwargs:kwargs.keys()
print(f(name='fentiao',age=10))
结果:dict_keys(['name','age'])
f = lambda **kwargs:kwargs.values()
print(f(name='fentiao',age=10))
结果:dict_values(['feniao',10])
"""
nums = [0, 7, 0, 1, 2, 1, 5, 1, 7, 8, 0, 67, 1, 3, 4]
"""
nums = [0, 7, 0, 1, 2, 1, 5, 1, 7, 8, 0, 67, 1, 3, 4]
print(sorted(nums,key=lambda x:1 if x == 0 else 0))
结果:[7,1,2,1,5,1,7,8,67,1,3,4,0,0,0]
"""
如何快速生成验证码,内推码
"""
import random
import string
code_str = string.ascii_letters + string.digits
print(code_str)
def gen_code(len=4):
return ''.join(random.sample(code_str,len))
# print(gen_code())
print([gen_code() for i in range(1000)]) //生成1000个4位数的验证码
![](https://img-blog.csdnimg.cn/20190122193035748.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3lpbnpoZW5fYm9rZV8wMzIx,size_16,color_FFFFFF,t_70)