C# BinarySearch如何在两个相邻的数组中查找值？

我有一个排序数组double。 目标是在数组中查找索引。

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它包含的值。当二进制搜索在数组中找不到项时，它返回一个负数，该负数是大于该值的第一个元素的索引的按位补码。以下是使用它查找范围的方法：

double[] spline_x = { 0D, 5D, 12D, 34D, 100D };
int i = Array.BinarySearch(spline_x, 25);
if (i >= 0)
{
    // your number is in array
}
else
{
    int indexOfNearest = ~i;

    if (indexOfNearest == spline_x.Length)
    {
        // number is greater that last item
    }
    else if (indexOfNearest == 0)
    {
        // number is less than first item
    }
    else
    {
        // number is between (indexOfNearest - 1) and indexOfNearest
    }     
}

不熟悉C#，但简单的二进制搜索就可以做到这一点，找到最后一个数字=end）{ 返回-1； } 大小\u t mid=（开始+结束）/2； 如果（v[mid]>num）{ //[mid，end]大于num，边界在[begin，mid]中 返回find_last（num、v、begin、mid）； }

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//v[mid]是合格的，谢谢。我有点简化：int I=Array.BinarySearch（spline_x，x）；如果（I=0）{}@Mixer记住，在递减I之后，你可以得到数组最后一项的索引

-1

double[] spline_x = { 0D, 5D, 12D, 34D, 100D };
int i = Array.BinarySearch(spline_x, 25);
if (i >= 0)
{
    // your number is in array
}
else
{
    int indexOfNearest = ~i;

    if (indexOfNearest == spline_x.Length)
    {
        // number is greater that last item
    }
    else if (indexOfNearest == 0)
    {
        // number is less than first item
    }
    else
    {
        // number is between (indexOfNearest - 1) and indexOfNearest
    }     
}

int find_last(int num, const vector<int>&v, size_t begin, size_t end) {
  if (begin >= end) {
    return -1;
  }
  size_t mid = (begin + end) / 2;
  if (v[mid] > num) {
    // [mid, end) is bigger than num, the boundary is in [begin, mid)
    return find_last(num, v, begin, mid);
  }
  // v[mid] is qualified as <= N, search [mid+1, end) for
  // approaching a better boundary if exists.
  size_t index = find_last(num, v, mid+1, end);
  return (index == -1 ? mid : index);
}