map()内置函数

首先，我们来看下map()内置函数的用法：

>>> help(map)
Help on class map in module builtins:

class map(object)
| map(func, *iterables) --> map object
|
| Make an iterator that computes the function using arguments from
| each of the iterables. Stops when the shortest iterable is exhausted.
|
| Methods defined here:
|
| __getattribute__(self, name, /)
| Return getattr(self, name).
|
| __iter__(self, /)
| Implement iter(self).
|
| __next__(self, /)
| Implement next(self).
|
| __reduce__(...)
| Return state information for pickling.
|
| ----------------------------------------------------------------------
| Static methods defined here:
|
| __new__(*args, **kwargs) from builtins.type
| Create and return a new object. See help(type) for accurate signature.

map()内置函数有两个参数，第一个参数为函数，第二个参数为可迭代对象，将可迭代对象中的每个元素作为函数的

参数进行运算，可以看到，第二个参数亦是一个收集参数，所以当第二个元素为收集参数时，其支持多个可迭代对象，

可迭代对象会依次取一个元素组成一个元组，然后传递给函数进行运算，当可迭代对象长度不一致时，到最短的那个

终止

例：

>>> list(map(lambda x:x**2,range(10)))
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

>>> list(map(lambda x,y:x+y,[1,8,10],[8,6,3,7,5,4]))
[9, 14, 13]