Same_Tree

/*
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.
*/
/**
 * Definition for binary tree
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
public:
    bool isSameTree(TreeNode *p, TreeNode *q) {
      if (!p && !q) return true;
      else if (!p) return false;
      else if (!q) return false;

      if (p->val==q->val) return isSameTree(p->left,q->left)&&isSameTree(p->right,q->right);
      else return false;
    }
};

REMARK:
1.Easy one. Typical binary tree question. Think in a recursive way.