6 . 851 : Advanced Data Structures Spring 2007 Lecture 7 — March 5 , 2007
نویسنده
چکیده
There are two primary models of temporal data structures. The first, called persistence, is based on the branching-universe model of time travel. In this model, going back in time and making changes creates a new branch of the data structure that differs from the original branch. The second, called retroactivity, works on the idea of round-trip time travel. Here, a time traveller goes back in time, makes a change, and then returns to observe the effects of his or her change. This model gives us a there is a linear timeline with no branching.
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