Paper summary: What are the main results of the paper? ========= Technical contribution: What are the key techniques used and/or introduced in the paper? ========= Strength: What is this paper's ``claim to fame''? Does it solve a longstanding open problem, present new techniques, overcome a technical barrier, or put forth a new research direction or model? ========= Weakness: This could include lack of originality, small increment over previous work, unsubstantiated claims, or bad presentation. ========= Opinion: The personal opinion of the reviewer about the paper. Did you like the paper? Are you interested in knowing more about the results of the paper, perhaps by attending a talk on this paper? Do you think the techniques of the paper are applicable to what other problems? What do you think was left unanswered by this paper and what is your favorite open question related to this paper? =========