What does > mean in this TAOCP solution?
What does > denote here?


It's not stated explicitly, but a reasonable meaning can be inferred from context.

The authors assume that the data can be sorted so there has to be some (total) order relation $\leq$ (canonically) on the elements. We don't care what the elements are, so we do not fix the relation, either. In any given situation, we would know what to do and have a fixed relation.

For instance, if we wanted to sort natural numbers in increasing order, $&gt;$ would mean the usual. I we wanted to sort them in decreasing order, you'd have to replace $&gt;$ by $&lt;$ in the solution.