Do You Know Your Abcs Silver #5787
Open
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Added explanation and implementation for USACO problem 1135.
eysbutno
reviewed
Dec 7, 2025
|
|
||
| Due to the low bounds, we can use a brute-force approach. There are seven labels $A$, $B$, $C$, $A + B$, $B + C$, $A + C$, and $A + B + C$. We need exactly $N$ of them, so we can iterate over all combinations of $N$ labels to decide which labels appear in this test case. | ||
|
|
||
| For a chosen set of labels, we need to decide which number corresponds to which label. We iterate over all permutations of the chosen labels, mapping them to the input array in order. Finally, we need to deduce the unique triple $(A, B, C)$ consistent with the mappings. To do this, we track candidate values for $A$, $B$, and $C$ using sets. If each of $A$, $B$, and $C$ has one consistent value, we record the triple as valid. |
Contributor
There was a problem hiding this comment.
should probably explain that we can always deduce a possible value for each variable based on its labels, because each variable (be it A, B, or C) is in 4 of the 7 variables, and we can at most get rid of 3 of them
at least i think that would help make the deduction idea more concrete
Contributor
Author
There was a problem hiding this comment.
yeah ill add that it should solidify the logic
Added a link to the official analysis for the problem.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Added explanation and Python implementation
Place an "x" in the corresponding checkbox if it is done or does not apply to this pull request.