Quick operations on the python list

In C, there is only one way to modify the content of each node in the container: traverse the node and perform operations on the node:

For (int I = 0; I <len; ++ I) {con [I] * = 2 ;}

Some of our C ++ 11 (m is a standard container ):

For (auto I: m) {I * = 2 ;}

Or

Foreach (m. begin (), m. end (), [] (x) {x * = 2 });

Naturally, someone will write in python like this:

For I in m: I = I * 2

If you are still writing like this for pythoner, you can do it in one sentence.

B = [x * 2 for x in a]

The list can be quickly generated in python, or even generated by conditional judgment.

C = [x * 2 for x in a if! = 2]

Well, it's a bit python.