The game of the trio, how to never lose: rules and strategies to win

The trio Is it a very popular game and can you play anywhere, but is there a way to always win? Spoiler … does not exist, but if you play carefully it is possible to never lose! We know because, as we will see, everyone (but everyone!) The possible ways in which a game can take place are known. We explain the rules of the game and then we see the “Fork strategy“With which you will not miss a game anymore, whether you are starting, whether you play for seconds!

How to play trio

The Tris is a game that can be played anywhere, just be two and trace two vertical lines cut by two horizontal lines, as in the figure, forming 9 squares (boxes).

Players choose a sign each, usually “דOr“⭘“, And in turn they occupy an empty box: the first one who manages to arrange 3 signs in a row (horizontal, vertical or diagonal) creates a trio And the game wins; If the boxes are all occupied without any player having obtained a trio, the game is equal.

There is a strategy to always win

The trio is a “Fixed game“, That is, a game of which all possible games are known: in the case of the trio it is known that there are 255168, many but not many! Most of these (131184 or 51.4%), end with the victory of the player who start, in 30.5% of cases (77904 games) wins the second player, while in the remaining 18.1% of cases (46080) the game ends in the same.

At this point one might think that, since all possible games are known, there is certainly a strategy to be used to always win, but it is not so, in reality There are only strategies that guarantee not to lose: using one of these strategies you can hope to win in the event that the opponent is fulfilled an error, but if everyone uses an optimal strategy, without errors, then the game will end in a tie.

How to win in Tris with the fork strategy

Let’s see the “Fork strategy“(This name is our free interpretation of the English original Fork) which will allow you to win in most cases where you will start a game and will allow you to equalize in the remaining cases, the important thing is to remember (in order of importance):

1. Of Start from a corner
2. If you have two signs in line (a potential trio) You can mark the third box For make a trio
3. If your opponent has two signs in line (a potential trio) you can mark the third box of the row for block the trio
4. Search for create 2 potential tris (which, however, do not share the empty box!) You will have won: this is the strategy of the fork.

If you start from a corner and your opponent does not respond by occupying the center then, using the strategy of the fork, you won! The strategy changes slightly based on your opponent’s responses, but just remember that you have to try to create 2 potential tris. In the event that your opponent respond by occupying the box under yours you can proceed like this (see figure below):

1. Occupy the corner at the top right: in this way you create a potential triobut at the same time you started creating yours fork
2. The opponent blocks your triootherwise you have won, but in this way he wastes a move.
3. Complete the fork (highlighted in green in the figure) occupying the corner at the bottom right: this way create 2 potential tris, And you won because your opponent can block a single trio for the next move.

In the event that your opponent responds by occupying other boxes, but not the central one, it will still be possible to create 2 potential trio, and therefore win, as shown in the synthesis of the figure below. In all cases, you will notice, you will have to play by occupying the boxes in the corners or the central one, but never the lateral ones.

But what if your opponent responds by immediately occupying the central box? Well, there are two possibilities, in the best of the cases you will win, in the worst case the game will end up in parity, always on condition that you play trying to create a fork occupying only corner boxesstarting from the opposite corner to the first you played, as shown in the figure below.

Can we win when it is not we who start?

The strategy we have seen allows you to win, or in the worst hypothesis to equalize, when we begin. But if you are not starting?

If your opponent also follows the Fork strategyor a similar strategy, we can only hope for the tie, but if it does not do it we can also hope for a victory. In all cases it is to try to create fork and prevent us from creating our opponent and to do so it is important not to make the first move:

• If our opponent begins by occupying a corner, you will have to occupy the central box
• In all other cases you will have to occupy a corner.

For subsequent moves try to bring you back to one of the situations we have described above aiming to occupy 3 corners or 2 corners and the center, but paying attention to prevent your opponent from being able to do it before you, otherwise you will have lost!