折半查找算法

int Binary_Search(S_T *t, KeyType kx)
{
  int low,high,mid;
  int flag;
  low=1;
  hight =t->length;
  falg = 0;
  while(low <= high)
  {
    mid=(low+high)/2;
    if(kx < t->data[mid].key)
      high=mid-1;
    else
       if(kx > t->data[mid].key)
         low=mid+1;
      else
      {
        flag=mid;
        break;
       }
    }
  return flag;
}