Do not get used to using namespace std

If you want to ask me what is the worst habit I found in C ++?

I have to tell you: it is the habit of using namespace STD;

Sometimes you will find that using namespace STD can save you a lot of time to avoid STD: cout; STD: CIN; STD: Endl, STD: String, etc,

I was fortunate to have discovered this secret for a while, but now I have discovered how fatal this secret is.

A few days ago, I used the simplest program to construct a read_info class and perform >>and <Operator overloading.

When I write a program, the habits are as follows:

# Include <iostream>

Using namespace STD;

Class read_info {

.......

};

When read_info.cpp calls read_info.h, the system prompts that the private member cannot be accessed.

Why am I surprised? Why can't I access my own members.

Later, we found that the most harmful tool is using namespace STD;

Of course, I have not made it clear: Why does it affect access by members?

But I must give up on this habit.