Problem Detail: How do we find all equivalence classes of $mathsf{R_L}$ for a language? Say I’m trying to look for all equivalent classes for the regular language $mathsf{L}$ is $011(0+1)^*011$. Here’s an example they give us in the book http://books.google.com/books?id=VEHYzv0GHt8C&pg=PA73&lpg=PA73&dq=ding+du+example+2.51&source=bl&ots=P8gAls0z7f&sig=HIsMb7rcD3hKZHYzi8fYZsyrLQ8&hl=en&sa=X&ei=5N0nUfSoJ6We2gWOv4HYDQ&ved=0CDMQ6AEwAA ps Read More …
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Finding the Largest “Ordered” Difference in Elements of an Array
Problem Detail: Suppose we are given an array of positive integers $P = [p_1, p_2, dots, p_N]$ where each $p_i$ represents the price of a product on a different day $i = 1 dots N$. I would like to design an Read More …
What is the difference between a TM accepting and deciding a language?
Problem Detail: Frankly I’m very uncomfortable with the material right now. There are some things I can understand, but many I still do not. My first assignment is asking me in one question (which I do know how to do) to Read More …
Finite automaton for the language of words whose second letter is b
Problem Detail: How can I build a finite automaton that accepts only the language of all words in which b is the second letter? This is my solution so far but I’m not sure if it’s correct. Asked By : Myles Canady Read More …
Is the complement of { ww | … } context-free?
Problem Detail: Define the language $L$ as $L = {a, b}^* – {wwmid w in {a, b}^*}$. In other words, $L$ contains the words that cannot be expressed as some word repeated twice. Is $L$ context-free or not? I’ve tried to Read More …
Priority queue with both decrease-key and increase-key operations
Problem Detail: A Fibonnaci Heap supports the following operations: insert(key, data) : adds a new element to the data structure find-min() : returns a pointer to the element with minimum key delete-min() : removes the element with minimum key delete(node) : Read More …
Is Dijkstras algorithm used in modern route-finding systems?
Problem Detail: Is Dijkstra’s algorithm used in modern route-finding systems such as Google maps or the satnav in your car? If not, then what is? Asked By : chopper draw lion4 Answered By : TinyProton Yes, Dijkstra’s algorithm is used in modern maps Read More …
How does a two-way pushdown automaton work?
Problem Detail: Note that by “two-way pushdown automaton”, I mean a pushdown automaton that can move its reading head both ways on the input tape. I recently had the question of determining the computational power of two-way PDAs in the Chomsky Read More …
Efficient algorithm for this optimization problem? Dynamic programming?
Problem Detail: I’ve created a diagram that depicts what I’m trying to accomplish. Full-size Image In the input sequence, the nodes are as close together as possible. But I want the white nodes to be as close to their respective black Read More …
What is the significance of context-sensitive (Type 1) languages?
Problem Detail: Seeing that in the Chomsky Hierarchy Type 3 languages can be recognised by a state machine with no external memory (i.e., a finite automaton), Type 2 by a state machine with a single stack (i.e. a push-down automaton) and Read More …
