Lights Out is a game played using 5x5 board. Each of the cell has a light which can either be in on or off state. Pressing a cell toggles the state (on becomes off, and off becomes on) of the pressed cell and also each of the adjacent cells (cells on the immediate left, right, above, and below). Note that a corner cell only has two neighbors and cells on the side has three.
A Lights Out game starts with the board showing a random pattern of cells and the goal of the game is to somehow make this board has all the lights turned off by pressing a set of cells/panels.
This puzzle cache uses the same board configuration, but with a couple of modifications:
1. The cells contain letters and digits to encode the offsets to obtain the final coordinates.
2. The top left cell in the corner is broken, meaning that pressing this cell will have no impact on the lights (it doesn't toggle any lights). However, not to worry, the light circuit of this broken cell is still functioning well, so its state can still be toggled by pressing the neighboring cells.
To solve this puzzle cache, you'll have to solve the Lights Out game presented below using minimum number of presses.
Examples: Pressing S0 will turn S0, A1, D9, I5, and W7 all on. Pressing T2 will turn off T2 and H0, but will turn on F4.
After you come up with the set of presses, you've probably figured out that it doesn't matter which order you press them, the solution will still be the same. However, for the purpose of this puzzle cache, you'll have to find out the proper arrangement of those pressed cells. Observing the set of pressed cells, you should be able to come up with an arrangement that stands out from the rest.
Once you got the proper ordering, concatenate the number digits in the odd-number positions together to form a number N. Similarly, concatenate the number digits in the even-number positions together to form a number W. Divide both N and W by 1000 and add them to the posted coordinates to get the final location.
You can check your answers for this puzzle on Geochecker.com.
You can validate your puzzle solution with certitude.
Congrats to Roktman for discovering the effective approach to the puzzle and the FTF