Welcome to Numbrail!

Numbrail is an exciting and strategic 5x5 optimization puzzle game that will challenge your tactical skills and numerical reasoning. Created by Wendly Saintil, this two-player game (or solo against the computer) is designed for fun and engaging gameplay. In Numbrail, your goal is to accumulate as many points as possible by strategically selecting numbers on the board.

Getting Started:

1. Understanding the Board:
   • The game begins with a 5x5 grid. At first, only the corner cells are open for selection.
   • Each cell contains a number ranging from 1 to 9. Some numbers may repeat on the board.
2. Taking Turns:
   • Players take turns making moves. The first player selects a number from an open cell, and the adjacent cells become open for the next player.
   • Players can only choose from open cells, and the game continues until all cells are selected.

Scoring:

1. Dividing Numbers:
   • After each move, the selected number goes to the player who made the selection.
   • The last selected number is divided between the two players.
   • If the number is even, both players receive half of the value.
   • If the number is odd, the player who made the last move receives the remainder, and the other player receives the quotient.

Strategies for Success:

1. Optimizing Moves:
   • Select numbers that will maximize your points while minimizing your opponent's potential gains.
   • Consider the potential future moves and how they will impact the distribution of points.
2. Blocking Opponent:
   • Pay attention to your opponent's moves and try to block their access to high-value cells.
   • Strategic blocking can limit your opponent's options and increase your chances of winning.
3. Adaptability:
   • Be flexible in your strategy based on the evolving state of the board.
   • Adjust your moves to maximize points while minimizing the opponent's opportunities.

Why Play Numbrail?

1. Engaging Gameplay:
   • Numbrail offers a unique and engaging gaming experience, combining strategy and numerical optimization.
2. Tactical Challenges:
   • The game challenges your ability to think ahead, adapt to changing situations, and make optimal decisions.
3. Solo Mode:
   • Enjoy a solo gaming experience by challenging yourself against the computer opponent.
   • Test your skills and strive to achieve the highest score on your own.
4. Friendly Competition:
   • Play against friends and family to enjoy friendly competition and strategic battles.

Game Dynamics (Example)

Numbrail is typically arranged in a grid configuration, and at the start of the game, the four corner cells are open. In this instance, these cells are denoted by the numbers 2, 4, 8, and 6.

At the beginning of the game, the cells containing the numbers 7, 5, 1, 9, and 3 are locked. It's worth observing that the central cell, marked with the number 1, is locked both vertically and horizontally.

Choosing the corner cell with the number 2 results in the unlocking of 7 and 5, as these two numbers are locked in one dimension.

Choosing the corner cell with the number 4 for the first move results in the unlocking of 7 and 9 instead.

Choosing the corner cell with the number 6 for the first move results in the unlocking of 3 and 9.

Choosing the corner cell with the number 8 unlocks 5 and 3. This is the best first move for this puzzle.

Notice how picking the number 5 unlocks the cell with number 1 horizontally. It is still locked vertically on the 7 or the 3.

Selecting 3 will now unlocks the inner cell with number 1 both vertically and horizontally.

Selecting 1 unlocks nothing. Number 9 is blocked by 4 or 6. And Number 7 is blocked by 2 or 4.

Observe how the selection of the number 4 would unlock both 7 and 9, as mentioned previously in the second example.

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Solution walkthrough

Now, let's explore the optimal solution for this example. It's important to note that there may be multiple solutions. (Score 23-22)

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Last selected number

The last chosen number is divided between the two players. In the case of the number 2, the distribution is equal, resulting in a 1-1 split. If the chosen number were 3, the split would have been 1-2.

Summary

Numbrail is not just a game; it's an opportunity to exercise your mind and enjoy a unique puzzle-solving experience. With its simple rules and deep strategic possibilities, Numbrail is perfect for players of all ages. So, dive in, make your moves wisely, and see who can emerge as the Numbrail champion!