export const SIZES = [100, 10_000] as const;

export function generateNumbers(size: number): number[] {
  return Array.from({ length: size }, (_, i) => i);
}

export function generateStrings(size: number): string[] {
  return Array.from({ length: size }, (_, i) => `item-${i}`);
}

/**
 * Generates indices that should be "error" slots, deterministically distributed.
 * With errRatio=0.2 and size=10, returns indices [4, 9] (every 5th element).
 */
export function errorIndices(size: number, errRatio = 0.2): Set<number> {
  const step = Math.max(1, Math.floor(1 / errRatio));
  const indices = new Set<number>();
  for (let i = step - 1; i < size; i += step) {
    indices.add(i);
  }
  return indices;
}