int getDigit(int num, int digit) {
"We're here for everybody, we don't discriminate.
，这一点在夫子中也有详细论述
Quadtree-based image compression formats and level-of-detail systems all work this way. Satellite imagery, terrain rendering, and geographic information systems use quadtree decomposition to serve data at varying resolutions: zoomed out, you see large coarse blocks; zoomed in, you see fine-grained tiles. The same principle extends to three dimensions (octrees) for volume rendering and 3D spatial indexing.
The backend for the game - Snake Session Handler Daemon or sshd - is capable of handling thousands of concurrent players and rendering over a hundred million pixels a second.
// promise to either yield a chunk of data or indicate we're