Python Primer: The Board

Before we can build an AI, we need a digital representation of the world. In Gomoku, our world is a 15x15 or 19x19 grid. In Python, the standard way to represent a grid is a List of Lists.

Concept: A Spreadsheet in Memory

Think of the outer list as the "spreadsheet" containing all rows. Each element inside it is another list representing the columns of that specific row.

Accessing Data

• board[0] returns the entire top row (a list).
• board[1][2] accesses Row 1, Column 2.

⚠️ Common Coordinate Error

In mathematics, we say $(x, y)$ where $x$ is horizontal and $y$ is vertical. In Python matrices, we access board[row][col].

Since "Row" corresponds to the vertical position ($y$) and "Col" to the horizontal ($x$), the code is effectively board[y][x]. Do not mix this up, or your AI will look at the board sideways!