vudduu's blog

By vudduu, 8 years ago, In English,
Problem Set and Data Set: Acm-icpc-latin-america-2011

- C - Candy's Candy (Math)
- E - Electrical Pollution (Graph Traversal)
- F - File Retrieval (Stack, Suffix Array)
- G - Garden Fence (Sweep Line)
- H - Hedge Mazes (Graph Bridges, Strongly Connected Components)
 
 
 
 
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8 years ago, # |
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C - Candy's Candy (math)
E - Electrical Pollution (graph traversal)
F - File Retrieval (stack, suffix array)

G - Garden Fence (sweep line)

H - Hedge Mazes (bridges)


Still clueless on D...

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    8 years ago, # ^ |
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    Oh thanks, i'm resolving the problem H.


    H - Hedge Mazes (Graph Bridges, Strongly Connected Components)
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    8 years ago, # ^ |
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    8 years ago, # ^ |
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    Can you give a hint on how to solve F using suffix array?
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      8 years ago, # ^ |
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      First concatenate all of the strings using invalid characters as separators, and construct the suffix array sa[] and the corresponding longest common prefix lcp[] array (where lcp[i] is LCP of sa[i] and sa[i+1]).

      It's easy to see that if you have a sequence of LCPs such as 1, 2, 3, 4, 2, 4, 1, in which 2 is less than or equal to all of the others, except the first and the last, then the words that contain the suffixes related to the 2,3,4,2,4 LCPs will form a searchable subset (there is a substring that appears in only those words). The stack is used to keep track of when those subsets are formed.
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    8 years ago, # ^ |
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    D - prefix/suffix trie + insights
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8 years ago, # |
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Are the solutions published anywhere? I found only tests but can't find the solutions :(