9.1.6 Checkerboard V1 Codehs Jun 2026

# Initialize the board board = []

This document analyzes the problem titled "9.1.6 checkerboard v1" from CodeHS (assumed exercise naming), reconstructs likely requirements, explains correct algorithmic approaches, provides a rigorous step‑by‑step solution, proves correctness, highlights edge cases, and offers an annotated reference implementation in Python (readable pseudocode for educators/students). Assumptions about the exact original prompt are made explicit where the source problem text is unavailable. 9.1.6 checkerboard v1 codehs

This is the most efficient way to handle alternating patterns in programming. # Initialize the board board = [] This

will fail the autograder. You must actually modify the list elements. Indexing Errors: Remember that Python indices start at grid has indices ranging from Middle Rows: Ensure rows will fail the autograder

function start() // Define the size of the board var NUM_ROWS = 8; var NUM_COLS = 8; // Outer loop handles the rows for (var row = 0; row < NUM_ROWS; row++) // Inner loop handles the columns for (var col = 0; col < NUM_COLS; col++) // Check if the sum of row and col is even if ((row + col) % 2 == 0) drawSquare(row, col, Color.red); else drawSquare(row, col, Color.black); function drawSquare(row, col, color) var sideLength = getWidth() / 8; var x = col * sideLength; var y = row * sideLength; var rect = new Rectangle(sideLength, sideLength); rect.setPosition(x, y); rect.setColor(color); add(rect); Use code with caution. Key Components Explained 1. Nested Loops

: Attempting to print the pattern directly instead of modifying the elements within a list structure. specific Python code