same fringe. For now, one straightforward way to determine this would be:
enumerate the fringe of the first tree. That gives you a list. Enumerate the
fringe of the second tree. That also gives you a list. Then compare the two
-lists to see if they're equal. (You just programmed this above.)
+lists to see if they're equal.
+
+Write the fringe-enumeration function. It should work on the
+implementation of trees you designed in the previous step, and it
+should make use of the list comparison function you wrote for question
+2. Thus you'll have to make sure you only use Church numerals as the
+labels of your leaves, though nothing enforces this self-discipline.
-Write the fringe-enumeration function. It should work on the implementation of
-trees you designed in the previous step.
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