There are four rules that decide a cell's next state:
-Empty cells (0, black) stay empty.
-Electron heads (1, blue) become electron tails.
-Electron tails (2, red) become conductors
-Conductors (3, green) become electron heads if exactly one or two of its neighbors are also electron heads. Otherwise they remain conductors
For each pair of stacked logic sources, the least significant bit is the lower one.
The bottom LED is the cell’s current state, and the top one is the calculated following state.
