Why using namespace is used in c++

Answer 1

please refer below link and may go through answers on this link:

https://www.sololearn.com/learn/CPlusPlus/1603/

Answer 2

If you're talking about "using namespace <namespaceName>" then that is to precache the used namespace(s) in the program.

Doing this can actually be a bad idea, and to many employers it is considered a bad practice to use "using namespace std;"