#include <iostream>
#include <memory>
#include <format>
#include <unistd.h>

using namespace std;


unsigned long long getTotalSystemMemory()
{
    long pages = sysconf(_SC_PHYS_PAGES);
    long page_size = sysconf(_SC_PAGE_SIZE);
    return pages * page_size;
}

int main(int argc, const char *argv[])
{
	auto size = getTotalSystemMemory()/4;
	
	std::unique_ptr<char []> p=std::make_unique<char[]>(size);
	
	while(true){
		auto new_size = size *1.1;
		try{
			p = std::make_unique<char []>(new_size);
		}catch(std::bad_alloc&){
			break;
		}
		size = new_size;
		std::cout<<std::format("{} bytes allocated ok.\n", size);
	}
	std::cout<<std::format("We believe {} bytes has been successfully allocated."
		"Now test writing each byte...\n", size);
	
	
	for(size_t i=0; i< size; ++i)
		p[i] = i%256;
	
	std::cout<<"Program finished normally!"<<std::endl;
	return 0;
}

9190172569 bytes allocated ok.
10109189825 bytes allocated ok.
11120108807 bytes allocated ok.
12232119687 bytes allocated ok.
13455331655 bytes allocated ok.
14800864820 bytes allocated ok.
16280951302 bytes allocated ok.
17909046432 bytes allocated ok.
Killed