Exercise 2.1 Write a function suffixes of type a list –> a list of list that takes a list xs and returns a list of all the suffixes of xs in decreasing order of length. For example,

suffixes [1,2,3,4] = [[1,2,3,4], [2,3,4], [3,4], [4], [ ] ]

Show that the resulting list of suffixes can be generated in O(n) time and represented in O(n) space.

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-module(e2_1).

-export([suffixes/1]).

suffixes(L) -> suffixes(L, []).

suffixes([H|T], R)
    -> suffixes(T, [[H|T]|R]);
suffixes([], R) -> lists:reverse([[]|R]).