A ja ešte doplním, že ak by tam malo byť viacero úrovní (teoreticky ľubovoľne veľký konečný počet), tak sa oplatí použiť tree traversal.
http://dev.mysql.com/tech-resources/art ... -data.html
http://php.vrana.cz/traverzovani-kolem- ... kticky.php
A. S. Tanenbaum píše:
The terms LF, MF, and HF refer to low, medium, and high frequency, respectively. Clearly, when the names were assigned, nobody expected to go above 10 MHz, so the higher bands were later named the Very, Ultra, Super, Extremely, and Tremendously High Frequency bands. Beyond that there are no names, but Incredibly, Astonishingly, and Prodigiously high frequency (IHF, AHF, and PHF) would sound nice.
