Learning C++ with Tetris

How to build:

clang++ -std=c++1z main.cpp -g -o tetris  -Wall

How to play:

./tetris

It starts immediately.

Following keys are available:

Cursor left	Move stone to left
Cursor right	Move stone to right
Cursor down	Move stone down
a	Rotate stone counter clock wise
s	Rotate stone clock wise
q	Quit game