```ts
/** The index of target in a sorted array, or -1. */
export function binarySearch(items: readonly number[], target: number): number {
  if (items.length === 0) {
    return -1;
  }
  let low = 0;
  let high = items.length - 1;
  while (low <= high) {    // Change the condition to include high
      const mid = Math.floor((low + high) / 2);
      if (items[mid] === target) {
        return mid;
      }
      if (items[mid] < target) {
        low = mid + 1;
      } else {
        high = mid - 1;
      }
    }
  return -1;
}
```