Leetcode---Same Tree

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

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

很像那个镜像的树，思想完全一样。

bool isSameTree(TreeNode *p, TreeNode *q) {
    if(p==NULL && q==NULL)
        return true;
    if(p==NULL || q==NULL)
        return false;
    return p->val==q->val && isSameTree(p->left,q->left) && isSameTree(p->right,q->right);
}