Same Tree

題目：

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.

代碼如下：

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