## 11393 - Tri-Isomorphism

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sonyckson
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### 11393 - Tri-Isomorphism

Well, i just wanna ask something, i did the "correct" solution ( at least the idea ) during the contest, but i thought the answer for input 1 was "YES" because you can have 3 empty lists of edges for each subgraph and ( as i see ) everything will be ok with the definitions given at the problem statement.... i got 2 WA during the contest, and another WA in another problem because of something similar, perhaps the same, i dont know what is it yet.... what im missunderstanding??? why the correct answer for input 1 is "NO"?? Thanks, Eric.

rio
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I did the exact same thing.

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Rio

sclo
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I'm pretty sure that any graphs with no edges are isomorphic to itself.

fh
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Can anyone explain the meaning of "three pairwise-isomorphic subgraphs"? and the two sample cases? I completely don't understand them.
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Felix Halim

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fh,

let three subgraph G1, G2 and G3
if G1 and G2 are isomorphic, and G2 and G3 are isomorphic and G3 and G1 are isomorphic
then this three are pairwise isomorphic subgraphs.

I think examples will be clear to you now.

fh
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Thx, emotional blind, just got it AC.
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yiuyuho
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### Re: 11393 - Tri-Isomorphism

sonyckson wrote:Well, i just wanna ask something, i did the "correct" solution ( at least the idea ) during the contest, but i thought the answer for input 1 was "YES" because you can have 3 empty lists of edges for each subgraph and ( as i see ) everything will be ok with the definitions given at the problem statement.... i got 2 WA during the contest, and another WA in another problem because of something similar, perhaps the same, i dont know what is it yet.... what im missunderstanding??? why the correct answer for input 1 is "NO"?? Thanks, Eric.
OK, so...why is the correct output for n=1 is NO? Is that a mistake?