LeeCode-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 a binary tree node.
  * struct TreeNode {
  *     int val;
  *     struct TreeNode *left;
  *     struct TreeNode *right;
  * };
  */
 bool isSameTree(struct TreeNode* p, struct TreeNode* q)
 {
     if(p==NULL&&q==NULL)
         return true;

     while(true)
     {
         if((p==NULL&&q!=NULL)||(p!=NULL&&q==NULL))
             return false;

         if(p->val!=q->val)
         {
             return false;
         }

         return isSameTree(p->left, q->left)&&isSameTree(p->right, q->right);

     }
     return true;
 }