[LinkedIn] Is Same Tree

/*
 * Check if two trees are the same
 */
public class Solution {
    public boolean isSameTree(TreeNode p, TreeNode q) {
        if(p == null && q == null) {
            return true;
        }
        if(p != null && q != null && p.val == q.val) {
            return isSameTree(p.left, q.left) && isSameTree(p.right, q.right);
        }
        return false;

    }
}