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CodeChef's January Challenge one problem wrong editorial??
By saurabhsuniljain, history, 8 years ago, In English

Problem : Rupsa and the Game Editorial : link

Wrong thing with Editorial :

But how many already existing sequence are there? Clearly, 2^(k−1) but when two pairs equal numbers are there then there will not 2^(k-1) sequences because of repetion of sequences, like suppose we have 1, 2, 2, 3, 3 We can obtain : 1 -> 1 2 -> 1 2 3 -> 2 1 2 3 -> 3 2 1 2 3 Also, : 1 -> 2 1 -> 3 2 1 -> 3 2 1 2 -> 3 2 1 2 3. So I think the approach is wrong and all have blind folded solved this problem.

I have also commented it there, but admin haven't replied yet. Can someone please check what I am saying is correct or not.

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8 years ago, # |
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Auto comment: topic has been updated by saurabhsuniljain (previous revision, new revision, compare).

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8 years ago, # |
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The problem statement mentions that 

Two gameplays are different, if after writing down all N + 1 numbers, when we read from left to right, there exists some position i, at which the gameplays have aj and ak written at the ith position such that j ≠ k

So what matters is the index of the number, and not the value. So even if we get the same values, they're considered different.

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