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Problem Detail: Let a binary counter with the operations INCREMENT and DECREMENT. I need to show that you can’t implement this kind of counter with constant amortized time per operation. Hence, I need to show that there’s a series of $N$ Read More …

Problem Detail: Context-free grammar can generate the string a 2 n for n≥0 . The production rule P is S→SS|a . The derivations is, for example: 1) S⇒a (this is when n = 0) 2) S⇒SS⇒aa (this is when n = Read More …

Problem Detail: Actually my question has two parts: 1) I wanted to know that whether Iterative Lengthening Search is used in combination with DFS or Uniform Cost Search? Actually, in Russell and Norvig book (on page 90), it is described as Read More …

Problem Detail: Here is a problem I am trying to solve: S -> 0A0 | 1B1 | BB A -> C B -> S | A C -> S | e I know that C is nullable (since it produces an Read More …

Problem Detail: I am studying “An Introduction to the Theory of Computation” by Sipser — there is a problem *3.17 (p.161) which I can not solve. Any hints (not answers) from which side to attack it? Let $B={M_1, M_2, …}$ be Read More …

Problem Detail: Both wikipedia and my lecturer explained how the 2 satisfiability problem work. However, I am finding it really hard understanding how this formula: xvy≡ ¬x–>y ≡ ¬y –>x Then breaks down the following conjectures : (¬x v y) & Read More …

Problem Detail: I have this code fragment: for( i=0; i<n; i++ ) for( j=0; j<i; j++ ) for( k=0; k<j; k++ ) S; I need to find the number of times that S is executed in that code block. I plugged Read More …

Problem Detail: Persistent data structures are immutable data structures. Operations on them return a new “copy” of the data structure, but altered by the operation; the old data structure remains unchanged though. Efficiency is generally accomplished by sharing some of the Read More …

Problem Detail: I am trying to find the maximum palindrome sub-sequence and after going through some tutorials, I came up with a memoized version.But I am not sure about the runtime.I want to know if the following algorithm will work.Could also Read More …