# Subtree of Another Tree

Given the roots of two binary trees root and subRoot, return true if there is a subtree of root with the same structure and node values of subRoot and false otherwise.

A subtree of a binary tree tree is a tree that consists of a node in tree and all of this node's descendants. The tree tree could also be considered as a subtree of itself.

```
public class Solution {
public boolean isSubtree(TreeNode s, TreeNode t) {
if (s == null) return false;
if (isSame(s, t)) return true;
return isSubtree(s.left, t) || isSubtree(s.right, t);
}
private boolean isSame(TreeNode s, TreeNode t) {
if (s == null && t == null) return true;
if (s == null || t == null) return false;
if (s.val != t.val) return false;
return isSame(s.left, t.left) && isSame(s.right, t.right);
}
}
```

## Related Problems

You are given the heads of two sorted linked lists list1 and list2.

Merge the two lists into one **sorted** list. The list should be made by splicing together the nodes of the first two lists.

Return *the head of the merged linked list*.

Given the root of a binary tree, flatten the tree into a "linked list":

The "linked list" should use the same TreeNode class where the right child pointer points to the next node in the list and the left child pointer is always null.

The "linked list" should be in the same order as a pre-order traversal of the binary tree.

Given the root of a binary tree, return *the inorder traversal of its nodes' values*.

Given the root of a binary tree, *check whether it is a mirror of itself* (i.e., symmetric around its center).