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Problem Detail: For the following two instruction [Note: MOV Destination, Source ] i1 : MOV R1, R2 i2 : ADD R2, R3 Since i1 is reading from R2 and i2 is writing to R2 there is a WAR data dependency and Read More …

Problem Detail: Polynomial identity testing is the standard example of a problem known to be in co-RP but not known to be in P. Over arithmetic circuits, it does indeed seem hard, since the degree of the polynomial can be made Read More …

Problem Detail: Is it necessary to remove all lambda productions, unit productions and useless productions from a context free grammar(CFG) before converting to Chomsky Normal Form(CNF) or Greibach normal form (GNF). If so why is it required? Also my Professor said Read More …

Problem Detail: $ALLEVEN_{CFG}$ = {M is a grammar, and L(M) includes all strings of even length in $Sigma^*$} = {(M): ($SigmaSigma$)* ⊆ L(M)} $ALLODD_{CFG}$ = {M is a grammar, and L(M) includes all strings of odd length in $Sigma^*$} = {(M): Read More …

Problem Detail: I did some quick math on how much data is contained on a screen at any given instant and I ended up with a number well beyond what I thought was possible. 256 colors for Red, Green, and Blue Read More …

Problem Detail: I know that $mathsf{P}^A = mathsf{EXP}$ for any $mathsf{EXPTIME}$-complete language $A$. Is it true that $mathsf{DTIME}^A(n^k) = mathsf{EXP}$ for any fixed $k$ and any $mathsf{EXPTIME}$-complete oracle $A$? If not, what do these complexity classes equal and why? I am Read More …

Problem Detail: Suppose that there are two problems $P$ and $Q$. How can I say that “solving $P$ is same thing with solving $Q$”? For instance, if $P$ is NP-Hard, then we can say “$P$ can be solved in polynomial time Read More …

Problem Detail: I’d like to reduce 3 colorability to SAT. I’ve stuffed up somewhere because I’ve shown it’s equivalent to 2 SAT. Given some graph $G = (V,E)$ and three colors, red, blue, green. For every vertex $i$, let the boolean Read More …