For this project, you will need to use the xlib system (part of XWindows) for a graphical user interface; attached is a code sample that opens a window, draws some line segments and arcs, and takes some input (but here I did not store the input and redraw it when the window changes; you will need to do that).
This works of course only on unix/linux machines (anything that has XWindows).
The programming language is C or C++.
It is already past deadline. I need it as soon as possible.
I can finish the project in 12 hours. I worked with C algorithm at university, so I have fresh knowledge. I have no freelance reviews, but please consider me as an option.