public class TreeNode {

int val;

TreeNode left;

TreeNode right;

TreeNode(int x) {

val = x;

}

}

/**

public static void main(String[] args) throws Exception {}

public boolean isSameTree(TreeNode p, TreeNode q) {

if ((p == null && q != null) || (p != null && q == null)) return false;

if (p == null && q == null) return true;

else {

boolean status = isSameTree(p.left, q.left);

if (!status || p.val != q.val) {

return false;

}

return isSameTree(p.right, q.right);

}

}