I would like to give some feedback about ...
i use a for loop in your shell, but when executed it skips some items of the list (pair items looks like).
i have attached an image where you can clearly see that it doesn't goes through all the numbers.
From: https://checkio.org/mission/non-unique-elements/solve/
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Created at: June 6, 2016, 10:16 a.m.; Updated at: June 6, 2016, 4:06 p.m.