Is same tree

//TODO

• http://www.programcreek.com/2012/12/check-if-two-trees-are-same-or-not/

public class Solution {
    public boolean isSameTree(TreeNode p, TreeNode q) {
        if(p == null && q == null){
            return true;
        }else if(p != null && q != null){
            if(p.val == q.val){
                return isSameTree(p.left, q.left) && isSameTree(q.right, p.right);
            }
        }else{
            return false;
        }

        return false;
    }
}