public T Search(MyLineTreeNode <T> parent, int left, int right)
{
//如果完全相等，则直接返回保存的值
if (left == parent.StartIndex && right == parent.EndIndex)
{
return(parent.SavedVal);
}
//中间索引
int mid = (parent.StartIndex + parent.EndIndex) / 2;
//如果要找的结束范围小于中间索引，在直接在节点左边树找
if (right <= mid)
{
return(Search(parent.Left, left, right));
}
//如果要找的开始范围大于中间索引，在直接在节点右边树找
else if (left > mid)
{
return(Search(parent.Right, left, right));
}
else
{
//否则两边都找
T leftObj = Search(parent.Left, left, mid);
T rightObj = Search(parent.Right, mid + 1, right);
return(CompareFunction.Invoke(leftObj, rightObj) ? leftObj : rightObj);
}
}
/// <summary>
/// 更改节点值
/// </summary>
/// <param name="index"></param>
/// <param name="weight"></param>
public void Change(int index, T val)
{
MyLineTreeNode <T> parent = Root;
//通过循环找到索引所在的节点
do
{
int mid = (parent.StartIndex + parent.EndIndex) / 2;
if (index <= mid)
{
parent = parent.Left;
}
else
{
parent = parent.Right;
}
} while (parent.StartIndex != index || parent.EndIndex != index);
//更改所在节点的值
parent.SavedVal = val;
//更改所在节点的值之后，需要调整所有父节点的值（通过不断和右边节点比较）
while (parent.Parent != null)
{
MyLineTreeNode <T> temp = parent.Parent;
temp.SavedVal = CompareFunction.Invoke(temp.Left.SavedVal, temp.Right.SavedVal) ? temp.Left.SavedVal : temp.Right.SavedVal;
parent = temp;
}
}
/// <summary>
/// 构造树
/// </summary>
/// <param name="start"></param>
/// <param name="end"></param>
/// <param name="ts"></param>
/// <returns></returns>
private MyLineTreeNode <T> BuildTree(int start, int end, T[] ts)
{
MyLineTreeNode <T> node = new MyLineTreeNode <T>(start, end, this.MaxValue, CompareFunction);
if (start < end)
{
int mid = (start + end) / 2;
MyLineTreeNode <T> left = BuildTree(start, mid, ts);
left.Parent = node;
node.Left = left;
MyLineTreeNode <T> right = BuildTree(mid + 1, end, ts);
right.Parent = node;
node.Right = right;
}
if (start == end)
{
node.Left = null;
node.Right = null;
node.SavedVal = ts[start - 1];
}
return(node);
}