type Tree struct {
data int
left *Tree
right *Tree
}
1. 镜像二叉树
func mirrorTree(root *Tree) *Tree {
if root == nil {return nil}
root.left, root.right = root.right, root.left
mirrorTree(root.left)
mirrorTree(root.right)
}
func mirrorTree(root *Tree) *Tree {
if root == nil {return nil}
mirrorTree(root.left)
mirrorTree(root.right)
root.left, root.right = right, root.left
return root
}
2. 二叉树最大深度
func maxLength(root *Tree) int {
if root == nil {return 0}
reutnr max(maxLenth(root.left,maxLentgh(root.right)), right) +1
}
3. 合并二叉树
func merge(r1, r2 *Tree) *Tree {
if r1 == nil {return r2}
if r2 == nil {return r1}
r1.val += r2.val
r1.Left = mergeTrees(r1.Left, r2.Left)
r1.Right = mergeTrees(r1.Right, r2.Right)
return r1
}