I think we have to have a practical definition of which group a point on the line is in.

You could go with neither, or both (I'd suggest "both").

It's neither. Otherwise, there's no way to satisfy the condition that either set contain at most half the points if the set contains an odd number of elements.

There's an analogy with the partition phase of quicksort: given a pivot, one divides the set of points into three: those points less than the pivot, those point greater than the pivot, and those equal to the pivot. One recurses into the first two groups.

Perl --((8:>*

In reply to Re^7: Puzzle: The Ham Cheese Sandwich cut. by Perl Mouse
in thread Puzzle: The Ham Cheese Sandwich cut. by Perl Mouse

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