DylanSp
• Member for 5 years, 10 months
• Last seen this week

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Original transactions: Insert record $r$. Update some field $f$ of $r$. Forward undo: Delete record $r$. Reverse the update to $r$ - oh wait, $r$ no longer exists! This causes an error.

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With only union and concatenation, you can't describe any infinite language. The union and concatenation can only produce finitely many strings. With only union and the Kleene star, you can't describe ...

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No, it's not possible, at least using the standard representations. An unsigned $n$-bit number can represent any integer in the interval $[0, 2^{n} - 1]$. A signed $n$-bit number using two's ...

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$2f$ and $2f + 1$ are just numbers. A set of $2f + 1$ nodes has a majority of non-faulty nodes, as you say; a set of $2f$ nodes can be deadlocked between the non-faulty and faulty nodes. A total of $... View answer 2 answers 2 votes 3k views 2 votes The inner loop will iterate$n - r + 1$times for each iteration of the outer loop. To find the total runtime, we can sum this expression over$r = 1$to$r = n: \begin{align*} \sum_{r = 1}^{n} (n - ... View answer 3 answers 1 votes 3k views 2 votes To expand on Denis's answer, the given automata is non-deterministic because it has\epsilon$-transitions. Because it's non-deterministic, given an input of the empty string$\epsilon$, we don't have ... View answer 4 answers 3 votes 898 views 2 votes Simply saying that$L$has the alphabet$\{x, y\}$and that no string in$L$contains the substring$xx$doesn't define a single language - there are infinite such languages. What you call expressing$...