sortedIndex

import { sortedIndex } from '@tulx/utils';

/**
 * Uses a binary search to determine the lowest index at which value should be inserted into array in order to maintain its sort order.
 *
 * @param array - The sorted array to inspect.
 * @param value - The value to evaluate.
 * @returns The index at which value should be inserted into array.
 *
 * @example
 * ```ts
 * sortedIndex([30, 50], 40); // 1
 * ```
 */
export function sortedIndex<T>(array: readonly T[], value: T): number {
  let low = 0;
  let high = array.length;

  while (low < high) {
    const mid = Math.floor((low + high) / 2);
    if (array[mid] < value) {
      low = mid + 1;
    } else {
      high = mid;
    }
  }

  return low;
}

import { sortedIndex } from '@tulx/utils';

sortedIndex([30, 50], 40); // 1