Problem 729. Flag largest magnitude swings as they occur

Created by Doug Hull

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You have a phenomenon that produces strictly positive or negative results.
delta = [1 -3 4 2 -1 6 -2 -7];
Marching through this list from beginning to end, mark a value with -1 if it is the greatest magnitude negative yet seen (strictly greater, not equal). Mark it with a one if it has the greatest magnitude in the positive direction (strictly greater, not equal). Just use a 0 if neither of these conditions have been met.
The result for the above example would be:
result = [1 -1 1 0 0 1 0 -1]

Solve

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Kevin Hellemans on 18 Sep 2013

The phrasing might be a bit ambiguous, as magnitude swing could also be thought of as delta(i-1)-delta(i) instead of just delta(i). Nonetheless fun problem!

Abhishek Jain on 16 Sep 2016

Nice question.

Abir Hasan on 1 Aug 2018

Nice problem

Josh on 7 Aug 2023

Agreed with first comment, it would be helpful to have more specificity with definition of magnitude "swing" ...perhaps the word "swing" is confusing because it implies some kind of reference point or change from one point to the next, when all that's being considered is the magnitude of each progressive value in comparison to previous max_magnitudes(+ and -)

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Problem 729. Flag largest magnitude swings as they occur

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Problem 729. Flag largest magnitude swings as they occur

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