On the Subject of Binary Grid

There are 10 types of people in the world : those who understand binary, and those who don’t.

  • The module consists of a 5×5 grid of zeroes and ones.
  • Each square can be switched between 0 and 1 when pressed, and the original state of the grid can be restored by pressing the “Reset” button.
  • The goal is to find the square to submit in three stages.
  • To submit an answer, push the “Submit” button and press the square of your choice.
  • Submitting an answer or pushing “Submit” again will get you out of submit mode.
  • The answer is in two parts : the row and column number.

Key generation

Primary key

The first step of solving any stage is to find the primary key of the stage. The key consists of a series of 6 zeroes and ones. At each of the following assertions, if the answer is true, then the corresponding number is 1, otherwise, it is 0.

First number Number of ones in the grid is even.
Second number Stage 1 : Number of batteries is even.
Stage 2 : There are 2 or more port plates.
Stage 3 : There are less than 2 lit indicators.
Third number Stage 1 : Number of ones is superior to the number of zeroes in the grid.
Stage 2 : Number of zeroes is superior to the number of ones in the grid.
Stage 3 : The number in the center square of the grid is a 1.

The last three numbers of the key are the same as the first three, with the 0 and 1 switched.

Secondary key

Using the primary key, you can now determine the secondary key of the stage. Below are different sets of grids with certain squares colored . After selecting the grid corresponding to your primary key, you can read the secondary key by associating the squares to the grid on the module and noting the values in those squares in reading order.


Solution part 1 : row number

With both keys, it is now possible to get the stage solution. For the row number, you need to count the number of ones and the number of zeroes in the two keys, and take the minimum between the two. You can then subtract x to that number to obtain the row number of the solution. x is determined as follows :

  • If there are strikes, x = 1.
  • Otherwise, x = 2.

NOTE : The number of strikes is counted when the stage solution is generated. That means that if a strike occurs during a stage, the solution will stay the same, and the strike will only be relevant for the next stage of the module.

Solution part 2 : column number

To find the column number, the primary key needs to be entered on the module, in the emplacements marked by the black squares. Once the key is entered, press the “Check” button. If the key has been correctly entered, the light above one of the columns should turn on, showing the column where the solution is. You can then submit the solution.