During processing a bunk of computation, people always eager to know how far from finish. The progress bar is exactly design for it. Console program does not support those fancy GUI, therefore something like below might be preferred. [======> ] 37%

DrawProgressBar.cpp

void DrawProgressBar(int len, double percent){
  std::string progress;
	bool firstSpace = true;
	for (int i = 0; i < len; ++i) {
		if (i < static_cast<int>(len * percent)) {
			progress += "=";
		} else {
			if (firstSpace)
			{
				progress += ">";
				firstSpace = false;
			}
			progress += " ";			
		}
	}
	
	std::printf("[%s] %d %% \r", progress.c_str(), static_cast<int>(100*percent));
	std::flush(std::cout); // Required.
}