I created a small web app puzzle game called "Euclidle" (/ˈjuːklɪdəl/) and I'd love for many people to enjoy it.
In this article, I'll briefly introduce how to play.
Basic rules
Here I'll explain the rules of the basic game type you can play on the game's top page.
In a virtual 3D space where the X, Y, and Z coordinates each range from 0 to 9, your goal is to find the hidden target coordinates within 6 guesses.
For an example of how to operate the game, please see the video below.
Near the center of the screen, you'll see "Coordinates" and "Euclidean distance" and each time you make a guess, colored squares appear.
These colored squares serve as hints.
The color is determined by how your new guess has moved relative to your previous guess with respect to the hidden target coordinates.
Suppose that, in a single dimension (a straight line), the correct answer is at the position of the green circle below.
In the explanations below, we'll call the previous guess "①" and the current guess "②".
A black square ⬛ indicates that either this is your first guess (so there is no previous guess to compare to), or that you guessed the same coordinates as last time, meaning there was no change in movement relative to the correct coordinates.
A blue square 🟦 indicates that, compared to the previous guess, your current guess is closer to the correct coordinates.
If your current guess exactly matches the correct coordinates, it will also be shown in blue.
A red square 🟥 indicates that, compared to the previous guess, your current guess is farther away from the correct coordinates.
If your previous guess was exactly correct and your current guess moved away from it, it will also be shown in red.
A yellow square 🟨 indicates that you first moved closer to the correct coordinates, and then moved farther away.
These colors are generally shared between the "Coordinates" display and the "Euclidean distance" display.
For more details, see the manual, but basically you use the above rules as clues to infer the position of the correct coordinates.
The number shown under "Euclidean distance" is the straight-line distance from your current guess to the correct coordinates.
It is the square root of the sum of the squared differences of each coordinate.
For example, if the correct coordinates are (X:7, Y:7, Z:7) and your current guess is (X:5, Y:6, Z:7), then the differences in each dimension are:
- Difference in X: 7 - 5 = 2
- Difference in Y: 7 - 6 = 1
- Difference in Z: 7 - 7 = 0
The sum of the squares of these differences is:
- 2^2 + 1^2 + 0^2 = 4 + 1 + 0 = 5
The square root of that value (the Euclidean distance) is:
- √5 = 2.2360679... ≒ 2.24
In the game, values are rounded to the nearest number at the third decimal place.
In the tutorial, I explain how to interpret the hints move by move using example problems, so please take a look.
On the game's top page, there is a daily game where players around the world all challenge the same hidden answer once per day.
If you'd like to play repeatedly, you can use Free Play with the same settings.
An easier game mode
If the rules above feel too difficult, there is also a simpler game mode, which I'll introduce below.
This mode is available under the menu item "Hint: Absolute mode (Easy)".
For example, you can play it from here.
In this rule set, the hint colors are not based on how your guesses "move" between two consecutive attempts, as in the previous rules, but solely on how close your current guess is to the correct coordinates.
Again, suppose that, in a single dimension (a straight line), the correct answer is at the position of the green circle below.
- If your guess matches the correct coordinate exactly, a green square 🟩 is displayed.
- If your guess is within two steps of the correct coordinate, a yellow square 🟨 is displayed.
- If your guess is three or more steps away from the correct coordinate, a black square ⬛ is displayed.
These colors are generally shared between the "Coordinates" display and the "Euclidean distance" display.
For more details, see the manual, but basically you use the above rules as clues to infer the position of the correct coordinates.
The number shown under "Euclidean distance" is the same as in the previous rule set.
In the tutorial, I explain how to interpret the hints move by move using example problems for this rule set as well, so please take a look.
