LeetCode(100)——Same Tree

題目：

Given two binary trees, write a function to check if they are the same or not.

Two binary trees are considered the same if they are structurally identical and the nodes have the same value.

 

兩個樹相等，即樹結構相等&&每個節點的數值相等。

 

AC:

    public boolean isSameTree(TreeNode p, TreeNode q) {
        if (p == q) {
            return true;
        }
        
        if (p == null || q == null) {
            return false;
        }
        
        return p.val == q.val && isSameTree(p.left, q.left) && isSameTree(p.right, q.right);
    }