https://leetcode-cn.com/problems/shu-de-zi-jie-gou-lcof/
func isSubStructure(_ A: TreeNode?, _ B: TreeNode?) -> Bool {
if A == nil || B == nil {return false}
//找到相同的跟节点
if A?.val == B?.val {
//比较子节点
return hasSubTree(A, B)
} else {
//寻找是否有相同的节点
return isSubStructure(A?.left, B) || isSubStructure(A?.right, B)
}
}
func hasSubTree(_ A: TreeNode?, _ B: TreeNode?) -> Bool {
if B == nil {return true}
if A == nil || A?.val != B?.val {return false}
return hasSubTree(A?.left, B?.left) && hasSubTree(A?.right, B?.right)
}
