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Open Claude Desktopprefix-sums · graph-algorithms · trees · data-structures
The organizer’s problem statement is available at the official source link.
sample trace
Sum of Distances: prefix sums walkthrough
Sum of Distances: use the linked editorial?s prefix sums, graph algorithms idea on the published sample, then verify the displayed output.
Published input2
2 1
1 2
4 4
1 2
2 3
3 4
4 1
3
4 4
1 2
2 3
3 1
3 4
6 5
1 2
2 3
3 4
4 5
5 6
7 7
1 2
2 3
3 4
4 5
5 6
6 7
7 1modelAlgorithm ideaStore cumulative aggregates so a range can be answered from two prefix values instead of rescanning its elements.task resultExpected output4
706
- 1
Accumulate
Build the running total or count across the input order. - 2
Query
Subtract the prefix before a range from the prefix at its end. - 3
Finish
Apply the task?s boundary adjustment and compare with the sample result. - 4
Verify the sample
Use the published sample output to check the result of this idea on the displayed input.
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Draft saved locally
|12 lines, 156 charsRun output
Run your code to see output.