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Talk:Order two numerical lists: Difference between revisions
→Is the task statement consistent?: Alternative wording sugestion
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:: Note that by convention, when we say "condition such and such for all i in set A" and A turns out to be empty, this condition is considered sastified.
:: Also note that, the task seems to have sorting in mind; however, if elements can be equal to each other, you ''must'' have a <math>\leq</math> comparison instead of <math><</math>, so equality also needs to be defined. The reason: a list <math>a</math> is considered sorted if for any pairs of indices <math>i, j</math> where <math>1 \leq i \leq j \leq M</math>, the condition is met: <math>a_i \leq a_j</math>. The last term can't be stated as <math>a_i < a_j</math> if elements may compare equal, or list (1, 2, 2) will not have a sorted permutation. --[[User:Ledrug|Ledrug]] 09:26, 30 November 2011 (UTC)
Seems to me then that my pseudo-code matches Ledrugs maths (thanks). The first quote from the task description is therefore wrong. Maybe it could be replaced with:
:''The function should accept two lists as arguments and return <code>true</code> if the first list lexicographically precedes or is equal to the second, or <code>false</code> otherwise.''
(Although it might invalidate earlier solutions). --[[User:Paddy3118|Paddy3118]] 17:45, 30 November 2011 (UTC)
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