Showing progress in command-line application

Ok, i am a bit embarrassed to ask such a simple thing but still.

I have command line utility application and need to implement showing progress to the user.

I could write progress into cout, like this:

std::cout << "10%\n";
 ...
 std::cout << "20%\n";
 ...
 std::cout << "30%\n";
 

... but as a result user will see:

some line printed before
 10%
 20%
 30%
 ...
 

... but what i really need is that percentage got updated
, like this at the beginning:

some line printed before
 10%
 ...
 

... and after update:

some line printed before
 20%
 ...
 

... and after second update:

some line printed before
 30%
 ...
 

How should i manage this?

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