Binary Gap

Erlang Binary Gap

-module(binary_gap).
-export([binary_gap/1]).

binary_gap(N) ->
    Bin = integer_to_list(N, 2),
    Trimmed = string:trim(Bin, both, "0"),
    Groups = string:split(Trimmed, "1", all),
    lists:max([length(G) || G <- Groups]).

This turns the number into binary, ignores zeroes outside the edges, and finds the longest run of zeroes between 1s.