bhagya.kjain's blog

Eolymp review
By bhagya.kjain, history, 18 months ago, In English

Is it worth to train on eolymp? Are problems well-set? Are there strong test cases?

Found some nice topic wise contest

Graphs — https://www.eolymp.com/en/contests/32919

Trees — https://www.eolymp.com/en/contests/30114, https://www.eolymp.com/en/contests/21224

Bipartite graphs — https://www.eolymp.com/en/contests/30008

0-1 BFS — https://www.eolymp.com/en/contests/26719

DSU — https://www.eolymp.com/en/contests/21411

DFS + Cycles + Cactus — https://www.eolymp.com/en/contests/21451

Flows and matching — https://www.eolymp.com/en/contests/21201

Topological sorting — https://www.eolymp.com/en/contests/21136

DFS — https://www.eolymp.com/en/contests/21097

Graph representation — https://www.eolymp.com/en/contests/21096

Sweeping line — https://www.eolymp.com/en/contests/20844

Dijkstra — https://www.eolymp.com/en/contests/19094

DP — https://www.eolymp.com/en/contests/17887

SCC — https://www.eolymp.com/en/contests/17029

Bitmasking DP — https://www.eolymp.com/en/contests/14738

Bridges, articulation points — https://www.eolymp.com/en/contests/12669

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18 months ago, # |
  Vote: I like it +9 Vote: I do not like it

Eolymp is a good platform, and problems there are of high quality. Some problems are either broken or just bad, but there are not many of these.

Overall, I'd recommend you do some specific problems there, like solving some past competitions. But I'd not suggest to use it as a daily training basis.

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18 months ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

How to solve this problem from eolymp?

I made these observations:

  • The number of subsets of cubes in input that make a block is quite small (for sure it's $$$\leq 1750$$$, maybe it's even smaller).
  • Then, we have to choose a subset of non-intersecting blocks that cover the whole solid.
  • It would be easy if we removed the condition "non-intersecting" (then, we could just use minimum bipartite vertex cover), but I think it's not possible. For example,
.@..
@@@@
.@..
.@..

can be covered with two blocks only if we allow them to intersect.

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