Problem Detail: You can get the Gödel number of a RAM by making it a list of commands and making this list an integer. So, what I thought is something like “The RAM that would return its own Gödel number (say, Read More …
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What does pre-, post- and in-order walk mean for a n-ary tree?
Problem Detail: The tree traversal methods explained in this Wikipedia article are pre-order, post-order and in-order. Are these methods limited to binary trees? The algorithm seems to be defined in terms of left and right child. If it can be used Read More …
What’s the difference between a rule based system and an artificial neural network?
Problem Detail: I’m currently doing some reading into AI and up to this point couldn’t find a satisfying answer to this question: what’s the difference between a rule based system and an artificial neural network? From my understanding both are trying Read More …
Extending the implementation of a Queue using a circular array
Problem Detail: I’m doing some exam (Java-based algorithmics) revision and have been given the question: Describe how you might extend your implementation [of a queue using a circular array] to support the expansion of the Queue to allow it to store Read More …
Show that every infinite language has a non-regular subset
Problem Detail: I’m trying to solve this problem: Let $L$ be some infinite language, show that there exists a sub-language of $L$ that is not regular But can this be correct? If I have the language ${a}^*$ for example, that’s infinite Read More …
Prove Queue Automaton is equivalent to Turing Machine
Problem Detail: A deterministic queue automaton (DQA) is like a PDA except the stack is replaced by a queue. A queue is a tape allowing symbols to be written (push) on the left-end and read (pull) on the right-end. Actually I’ve Read More …
How to make a parse tree for the following propositional logic formula?
Problem Detail: I have a formula $ neg((q implies neg q) vee p vee (neg q implies (r wedge p))) $. As it contains 3 subformulas between the $vee$’s, how can i put it into a parse tree, as a parse Read More …
DNF to CNF conversion: Easy or Hard
Problem Detail: In relation to the thread CNF to DNF — conversion is NP Hard (and a related Math thread): How about the other direction, from DNF to CNF? Is it easy or hard? On Page 2 of this paper, they Read More …
Converting CFG to PDA
Problem Detail: I have the following CFG, $S rightarrow CB$ $C rightarrow aCa text{ }|text{ } bCb text{ }|text{ } text{#}B$ $B rightarrow AB text{ }|text{ } varepsilon$ $A rightarrow atext{ }|text{ }b$ This is the CFG for the following language: Read More …
CFG for ${a^ib^jc^k mid i neq j+k}$
Problem Detail: I am trying to design a context-free grammar for the language $L = {a^ib^jc^k mid ineq j+k}$ over the alphabet $Sigma = {a,b,c}$. I know that I can split this up into the union of two cfg’s $S_1$ and Read More …
