C++ output 的就地计数器

Question

I'd like to format the output of my program to print a number (index) then some text, and the number incriments as the program progresses. I'm using CLion, but I'd be interested to know if any solutions are 'universal'.

I've experiemted with flushing the output and system CLS:

cout << i << ".  has been checked" << flush;
cout << system ("CLS");

in a few different configurations but I get the feeling this is not the way.

Answer 1

Formally, there's no answer, but quite a few systems support \b for backspace.

It's a good programming exercise to try this - remember that you need to backspace each digit that's been printed. So when you go from 99 to 100, you need \b\b . And if you increment by varying steps (eg for "bytes downloaded") you need to keep track of how many digits are already on the screen.

Answer 2

Assuming that the vertical position of the output never changes, use a carriage return character ( \r ) for this.

std::cout << "\r" << i << ".  has been checked";

The \r just sets the position of the cursor to the beginning of the line.

If this doesn't do what you want, or you are outputting text after writing out i , then you need a more platform specific solution; move/wmove with ncurses on Linux and SetConsoleCursorPosition on Windows, for example.