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Count trailing truths

Inspired by, and in memory of, my dear friend and colleague,

Dan Baronet

Dan Baronet, 1956 – 2016. R.I.P.

He found the shortest possible APL solution to this task:

Task

Given a Boolean list, count the number of trailing truth values.

Example cases

{} → 0

{0} → 0

{1} → 1

{0, 1, 1, 0, 0} → 0

{1, 1, 1, 0, 1} → 1

{1, 1, 0, 1, 1} → 2

{0, 0, 1, 1, 1} → 3

{1, 1, 1, 1, 1, 1} → 6

Answer*

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…Be sure to follow the challenge specification. However, please refrain from exploiting obvious loopholes. Answers abusing any of the standard loopholes are considered invalid. If you think a specification is unclear or underspecified, comment on the question instead.
…Try to optimize your score. For instance, answers to code-golf challenges should attempt to be as short as possible. You can always include a readable version of the code in addition to the competitive one. Explanations of your answer make it more interesting to read and are very much encouraged.
…Include a short header which indicates the language(s) of your code and its score, as defined by the challenge.

More generally…

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2

\$\begingroup\$ Hint: This can be done in only 3 bytes, using the J translation of Dan's solution. \$\endgroup\$

Adám
– Adám

2016年11月06日 17:25:21 +00:00
Commented Nov 6, 2016 at 17:25
1

\$\begingroup\$ @Adám I tried looking for a solution. Didn't think of base conversion. That's really quite clever of him! \$\endgroup\$

Conor O'Brien
– Conor O'Brien

2016年11月06日 18:44:52 +00:00
Commented Nov 6, 2016 at 18:44
1

\$\begingroup\$ Yes. That was Dan. :-( \$\endgroup\$

Adám
– Adám

2016年11月06日 19:20:48 +00:00
Commented Nov 6, 2016 at 19:20

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