C#二分查找算法实例分析

本文实例讲述了c#二分查找算法。分享给大家供大家参考。具体实现方法如下：

// input array is assumed to be sorted
public int binarysearch(int[] arr, int x)
{
 if (arr.length == 0)
  return -1;
 int mid = arr.length / 2;
 if (arr[mid] == x)
  return mid;
 if (x < arr[mid])
  return binarysearch(getsubarray(arr,0,mid-1),x);
 else
 {
  int _indexfound = binarysearch(getsubarray(arr,mid+1,arr.length-1),x);
  if (_indexfound == -1)
   return -1;
  else
   return mid + 1 + binarysearch(getsubarray(arr,mid+1,arr.length-1),x);
 }
}
public int[] getsubarray(int[] arr, int start, int end)
{
 list<int> _result = new list<int>();
 for (int i = start; i <= end; i++)
 {
  _result.add(arr[i]);
 }
 return _result.toarray();
}

希望本文所述对大家的c#程序设计有所帮助。