Quickfuck is an optimizing brainfuck interpreter. It does however not yet support more than the standard brainfuck dialect.
If you are using MacOS or Linux, just open the command line, move to the 'src'-directory and run 'make'. This should create an executable file called 'qf'.
If you are using Windows and have g++ installed, open cmd.exe and move to the 'src'-directory. Now run this command:
g++ *.cpp -O3 -o qf.exe
Now there should be an executable file called 'qf.exe'
Run the program in the command line. You can specify a file as an argument which is then executed. Alternatively you can run the program and enter the code then. To start the execution, submit the code with an EOF-character (Ctrl+D on most unix-like systems, Ctrl+Z on Windows).
There are a few things important to note when pushing it to the limit:
The memory is not guaranteed to be aligned in a circular way, i.e. when executing the following program +[>+] it will probably exit with a segmentation fault. If you need the memory to be aligned in a circular way, run quickfuck with argument '-i' which will run quickfuck in interpret-only mode. However, running quickfuck in this mode is generally a lot slower than otherwise, which is why it is normally better to avoid it.