Kaggle's Conway's Reverse Game of Life contest inspires this Reverse Life Zoo challenge. The kaggle contest runs from Oct-14-2013 thru Mar-02-2014. References: Game of Life at Wolfram. Wiki Life.

1. Any live cell with fewer than two live neighbors dies, as if caused by under-population.
2. Any live cell with two or three live neighbors lives on to the next generation.
3. Any live cell with more than three live neighbors dies, as if by overcrowding.
4. Any dead cell with exactly three live neighbors becomes a live cell, as if by reproduction.
5. No wrap around. Beyond edge is zero. Eight Neighbors.

Determine the Zoo of life at its previous Snapshot. The output must evolve to the given Zoo Snapshot. It is a Zoo since all animals are in their private enclosures and do not interact with any other animals. Animals are stable or cyclic oscillators.

Input: Zoo , an [m,n] array

Output: ZooPre, image of the Zoo at its prior iteration

Example:

Zoo        ZooPre
0000000000  000000000  
0110000100  011000000  
0110000100  011001110  
0000000100  000000000  
0000000000  000000000

Additional References: Oscillators, Still Life

Next: Small Island - Prior Snapshot Prediction