我有以下二叉树，我正在尝试使用最少数量的树旋转将其转换为目标二叉树（帖子中的第二个树）。这棵树的理论最小旋转数是5，但是，我能算出的最小值是6次旋转，我也复制了旋转，我缺少什么？
树：
1
\
\
3
/ \
/ \
2 5
/ \
/ \
4 7
/ \
/ \
6 11
/ \
/ \
9 12
/ \
8 10
目标树
1
\
\
11
/ \
/ \
9 12
/ \
/ \
3 10
/ \
/ \
2 5
/ \
/ \
4 7
/ \
6 8
到目前为止我尝试过的旋转（所有旋转都需要6次旋转）：
Order1：
Rotate left with root 7 and pivot 11
Rotate left with root 5 and pivot 11
Rotate left with root 3 and pivot 11
Rotate left with root 7 and pivot 9
Rotate left with root 5 and pivot 9
Rotate left with root 3 and pivot 9
的 Order2：
Rotate left with root 7 and pivot 11
Rotate left with root 5 and pivot 11
Rotate left with root 7 and pivot 9
Rotate left with root 3 and pivot 11
Rotate left with root 5 and pivot 9
Rotate left with root 3 and pivot 9
Order3：
Rotate left with root 7 and pivot 11
Rotate left with root 5 and pivot 11
Rotate left with root 7 and pivot 9
Rotate left with root 5 and pivot 9
Rotate left with root 3 and pivot 11
Rotate left with root 3 and pivot 9
Order4：
Rotate left with root 7 and pivot 11
Rotate left with root 7 and pivot 9
Rotate left with root 5 and pivot 11
Rotate left with root 3 and pivot 11
Rotate left with root 5 and pivot 9
Rotate left with root 3 and pivot 9
Order5：
Rotate left with root 7 and pivot 11
Rotate left with root 7 and pivot 9
Rotate left with root 5 and pivot 11
Rotate left with root 5 and pivot 9
Rotate left with root 3 and pivot 11
Rotate left with root 3 and pivot 9
答案 0 :(得分：1)
用根11和枢轴9向右旋转
向左旋转，带根部7和枢轴9
用根5和枢轴9左旋转
向左旋转，用根3和枢轴9
向左旋转，用根9和枢轴11