/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
class Solution {
    public boolean hasSubtree(TreeNode pRoot1, TreeNode pRoot2) {
       if (pRoot1 == null || pRoot2 == null) {
           return false;
       }

       return isSubtreeWithRoot(pRoot1, pRoot2) || hasSubtree(pRoot1.left, pRoot2) || hasSubtree(pRoot1.right, pRoot2);
    }

    private boolean isSubtreeWithRoot(TreeNode pRoot1, TreeNode pRoot2) {
        if (pRoot2 == null) {
            return true;
        }
        if (pRoot1 == null) {
            return false;
        }
        if (pRoot1.val != pRoot2.val) {
            return false;
        }
        return isSubtreeWithRoot(pRoot1.left, pRoot2.left) && isSubtreeWithRoot(pRoot1.right, pRoot2.right);
    }
}