Re:The World Excel Championship is being broadcast on ESPN
by sanedigital on Thursday August 11, 2022 @10:13AM
(#32425898)
Not sure I agree. It's very simple if you look at what's "wrong" with the input: it has a duplicated number, which means there's a "right" version of it without. That right version is just the count from 1->n. Once you see that, you can see that all you have to do is sum each list and calculate the difference.
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Re:The World Excel Championship is being broadcast on ESPN
by kd5bjo on Thursday August 11, 2022 @10:18AM
(#32426005)
This algorithm fails in the case that the duplicated number appears more than twice in the list, which is explicitly allowed by the problem statement.
Re:The World Excel Championship is being broadcast on ESPN
by sanedigital on Thursday August 11, 2022 @01:11PM
(#32428819)
It’s not, on Leetcode. I submitted it as an answer and it worked. In the case where the number is repeated more than once (m times), you have an array of n+m elements. Divide the sum by m, subtract, problem solved.
Re:The World Excel Championship is being broadcast on ESPN
by kd5bjo on Thursday August 11, 2022 @02:10PM
(#32429618)
In that case, their test suite doesn’t cover all relevant cases. Consider nums = [1,1,1,1,4]: There are 5 elements, so n=4, and all elements are within the range [1,4]; only the 1 is duplicated. This fulfills all of the listed requirements.
The actual sum is 8, and the 4th triangular number is 10, so the duplicated number according to your algorithm must be -2 (or some fraction thereof, depending on how you calculate m).