# Recent posts tagged interview-experience

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Can you please give any source which contain r(*)=r*.Previous year question book gave answer b and their b is (r*s*)*=(r+s)*
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i think the language would be L= 00(0000)* if L= 00 + (0000)* then 0000 cant reaches the final state .
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No. $\begin{array}{|c|c|c|} \hline \text {A} & \text {B} & \text {C} \\\hline\text {1} & \text {5} & \text {6} \\\hline\text {2} & \text {4} & \text {7}\\\hline \text {3} & \text {4} & \text {5}\\\hline \end{array}$ Suppose this is the relational ... hold for $R.$ PS: If we have a single instance where $A \to BC$ is not holding, it is enough to say $A \to BC$ does not hold for the relation $R.$
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R1,R2 has common attribute B. B is key in R2. so R1(AB) R2(BC) composed into R12(ABC) Between R12(ABC) and R3(CD) common attribute is C and C is key in R3. Hence the decomposition is lossless. Checking dependency preservation. R1(AB) R2(BC) R3(CD) A->B B->C C->D We ... if D->A is covered by G D+={DA} D+ in G ={DCBA} hence D->A is also preserved. Hence loss-less as well as dependency preserving.
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Why we have considered without replacement here? Can't this be like ...... 1/3 * (4/12 * 3/12) / [1/3 * (4/12 * 3/12 ) + 1/3 * (2/4 * 1/4 ) + 1/3 * (1/6 * 3/6 )] ?
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Which of the following describes the minimum condition for ambiguity in a grammar? a) Every derived word must have atleast 2 rightmost derivation b) some word must have more than 1 leftmost derivation c)A derived word has one rightmost and another leftmost derivation d)each derived word has 2 leftmost and 2 rightmost derivation
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lets rename the attributes a) Let Bookid=A,subject-category-of-book=B,Name-of-author=C,Nationality-of-Author=D A is the Pk hence A+={BCD} F .D is A->BCD Since there is one attributed CK,there is no prime attribute hence,no partial dependency,so Relation is 2NF No transitive ... b)Let Book-Title=E Author-Address=F CE->ABD ce is PK There is a non trivial dependency and LHS of which is SK so BCNF.
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If r is a relation on a then it's xsitive closure = the smallest xsitive relation on a which contain r ...eg a={a,b,c} and r= {(a,c),(c,b)} then r* = { (a,c),(c,b),(a,b)}
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option A C$\Rightarrow$ a or, C $\Rightarrow$b or, C $\Rightarrow$aCb$\Rightarrow$aaCbb$\Rightarrow$ aaaCbbb .. soon at last you have to put either C$\rightarrow$ a or C$\rightarrow$ b so production C is used to derive $a^{n+1}b^{n}$ or $a^{n}b^{n+1}$ $n \geq 0$ S$\rightarrow$ AC [Aanbn+1] ... $\rightarrow$ CB will generate $a^{n}b^{n}b^{+}$ i.e $a^{i}b^{j} \ i<j$ option D is right .
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A only. B is false as for a single tuple, dname cannot be both 'shoe' as well as 'toy' and hence this query returns {}.
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If you put "Null" as introducer it will work. But by self introduction I mean "john" introducing himself- introducer will be "john" for customer "john". But I guess this needn't be considered unless specified as by the meaning of "introduction" we can assume it is a different person.
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A machine needs a minimum of 100 sec to sort 1000 names by quick sort. The minimum time needed to sort 100 names will be approximately 50.2 sec 6.7 sec 72.7 sec 11.2 sec
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Answer: B Round Trip Time $= 80ms$ Frame size $=32\times 8\text{ bits}$ Bandwidth $=128\text{ kbps}$ Transmission Time $=\dfrac{32\times 8}{128}\ ms = 2\ ms$ Let $n$ be the window size. Utilization $=\dfrac{n}{1+2a}$ where $\large a = \dfrac{\text{Propagation Time}}{\text{Transmission Time}}$ $=\dfrac{n}{1+\dfrac{2 \times 40}{2}}$ For maximum utilization: $n = 41$ which is close to option (B).
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Thank u sir :)
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starting with 001100110011 means alternative sequence of process P and Q.. Process P should start execution so at W, P(s) where S=1.. to get alternate sequence X and Y are operation on same semaphore i.e. T. option B or C. bt process Q shouldn't start execution before process P .. means Initial value T=0 W : P(s) X : V(T) Y : P(S) Z : V(S) S = 1 T = 0
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Among simple LR (SLR), canonical LR, and look-ahead LR (LALR), which of the following pairs identify the method that is very easy to implement and the method that is the most powerful, in that order? SLR, LALR Canonical LR, LALR SLR, canonical LR LALR, canonical LR
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Option A is correct because height $5$ means level $6$ so maximum node $= 2^l -1 =2^6 -1=63$ and for minimum, at each level only single node so total $6$.
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The number of onto functions (surjective functions) from set $X = \{1, 2, 3, 4\}$ to set $Y=\{a,b,c\}$ is ______.
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A system has $6$ identical resources and $N$ processes competing for them. Each process can request at most $2$ requests. Which one of the following values of $N$ could lead to a deadlock? $1$ $2$ $3$ $4$
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If $g(x) = 1 - x$ and $h(x) = \frac{x}{x-1}$, then $\frac{g(h(x))}{h(g(x))}$ is: $\frac{h(x)}{g(x)}$ $\frac{-1}{x}$ $\frac{g(x)}{h(x)}$ $\frac{x}{(1-x)^{2}}$
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C) P - iii, Q - i, R - iv, S - ii Ref: https://en.wikipedia.org/wiki/Software_testing
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Is there any SQL command which belongs to both DDL and DML?
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Answer is D. $L_1$ is context-free and hence recursive also. Recursive set being closed under complement, $L_1$' will be recursive. $L_1$' being recursive it is also recursively enumerable and Recursively Enumerable set is closed under Union. So, $L_1' \cup L_2$ is recursively enumerable. ... $L_2$')' $= L_2$ is also recursive which is not the case here. So, $II$ is also false.