When implementing algorithms that involve spacing, gaps, or iterative calculations, carefully verify loop bounds and edge cases to prevent off-by-one errors. These errors commonly occur when calculating spacing between N items (which requires N-1 gaps, not N gaps) or when applying operations to boundary elements. Key areas to scrutinize: - Gap calculations: For N items, there are N-1 gaps between them - Boundary conditions: Verify first/last element handling - Division operations: Check for zero denominators and edge cases - Loop iterations: Ensure correct start/end conditions Example from gap calculation: ```cpp // Wrong: adds gap for all children (N gaps for N items) for (int i = 0; i < childCount; i++) { mainDim += childSize + betweenMainDim; } // Correct: adds gap only between children (N-1 gaps for N items) const bool isLastChild = i == childCount - 1; if (isLastChild) { betweenMainDim -= gap; // Remove gap for last item } ``` Always validate your algorithm with boundary cases: single item, empty collection, and maximum expected size. Consider whether conditional checks like `if (lineCount > 1)` are truly necessary or artifacts of avoiding edge case bugs.