Problem Detail: Sorry in advance if this question sounds dumb… As far as I know, building an algorithm using dynamic programming works this way: express the problem as a recurrence relation; implement the recurrence relation either via memoization or via a Read More …
Author: ignougroup
Intersection/Union of recursively enumerable languages that aren’t decidable?
Problem Detail: For $L_1, L_2 $ and $L_1 in RE $ and $ L_1notin R$ and $L_2 in RE $ and $ L_2notin R$ I was asked to prove/disprove if the following can occur: $L_1 cap L_2 in R$ $L_1 cup Read More …
Would proving P≠NP be harder than proving P=NP?
Problem Detail: Consider two possibilities for the P vs. NP problem: P=NP and P$neq$NP. Let Q be one of known NP-hard problems. To prove P=NP, we need to design a single polynomial time algorithm A for Q and prove that A Read More …
Finding a O(n) solution to: max difference of pairs array question
Problem Detail: I don’t know an O(n) solution to the following: Given an array of n integers, find the largest difference between any two pairs in the array: however, the larger integer must have a higher index in the array than Read More …
How is a JIT compiler different from an ordinary compiler?
Problem Detail: There’s been a lot of hype about JIT compilers for languages like Java, Ruby, and Python. How are JIT compilers different from C/C++ compilers, and why are the compilers written for Java, Ruby or Python called JIT compilers, while Read More …
Huffman encoding: why is there no need for a separator?
Problem Detail: Char Code ==== ==== E 0000 i 0001 y 0010 l 0011 k 0100 . 0101 space 011 e 10 r 1100 s 1101 n 1110 a 1111 Original text: Eerie eyes seen near lake Encoded: 0000101100000110011100010101101101001111101011111100011001111110100100101 Why Read More …
How do you classify properties as Trivial and Non-trivial?
Problem Detail: I understand what Rice’s theorem states and what Trivial and Non-trivial properties mean. However, when given some property, I am having a hard time seeing if it is Trivial or Non-trivial. Can someone help me understand this better, maybe Read More …
Measuring one way network latency
Problem Detail: This is a puzzle about measuring network latency that I created. I believe the solution is that it’s impossible, but friends disagree. I’m looking for convincing explanations either way. (Though it is posed as a puzzle I think it Read More …
Proof Complexity of a Proof or Disproof of P = NP
Problem Detail: Has there been any research on the proof complexity of a resolution to the P=NP problem? If not, given the lack of progress on the problem, would it be unreasonable to conjecture that any proof that resolves the P=NP Read More …
I need clarification about DFA’s and DFA acceptable languages
Problem Detail: In class yesterday we went over DFA’s and DFA acceptable languages. An example of a language that is not DFA acceptable was given as ${ ab, aabb, aaabbb, aaaabbbb, ldots }$. The reason given was that the machine would Read More …
