js实现二分查找算法

  binarySearchIndex(array, target) {
    let high = array.length - 1
    let low = 0
    while (low <= high) {
      let mid = (high + low) >>> 1
      let midVal = array[mid]
      console.log('当前mid', mid)
      if (midVal == target) {
        return mid
      } else if (midVal > target) {
        high = mid -1
      } else {
        low = mid + 1
      }
    }
    return -1
  }