# Recent questions tagged gate1998 5 votes
2 answers
1
Let $R$ be a binary relation on $A = \{a, b, c, d, e, f, g, h\}$ represented by the following two component digraph. Find the smallest integers $m$ and $n$ such that $m < n$ and $R^m = R^n$.
19 votes
3 answers
2
Solve the following recurrence relation $x_n = 2x_{n-1}-1, n>1$ $x_1=2$
4 votes
4 answers
3
Consider a disk with $c$ cylinders, $t$ tracks per cylinder, $s$ sectors per track and a sector length $s_l$. A logical file $d_l$ with fixed record length $r_l$ is stored continuously on this disk starting at location $(c_L, t_L, s_L)$ ... . Derive the formula to calculate the disk address (i.e. cylinder, track and sector) of a logical record n assuming that $r_l=s_l$.
34 votes
9 answers
4
Compute the post fix equivalent of the following expression $3^*\log(x+1)-\frac{a}{2}$
39 votes
5 answers
5
In a computer system where the best-fit' algorithm is used for allocating jobs' to memory partitions', the following situation was encountered:$\begin{array}{|l|l|} \hline \textbf{Partitions size in$KB$} & \textbf{$4K \ 8K \ 20K \ 2K$} \\\hline \textbf{Job sizes in$KB$} & \text{$2K ... $} \\\hline \end{array}$When will the $20K$ job complete?
20 votes
5 answers
6
Give a regular expression for the set of binary strings where every $0$ is immediately followed by exactly $k$ $1$'s and preceded by at least $k$ $1$’s ($k$ is a fixed integer)
27 votes
10 answers
7
Consider the following relational database schemes: COURSES (Cno, Name) PRE_REQ(Cno, Pre_Cno) COMPLETED (Student_no, Cno) COURSES gives the number and name of all the available courses. PRE_REQ gives the information about which courses are pre-requisites for a ... following using relational algebra: List all the courses for which a student with Student_no 2310 has completed all the pre-requisites.
45 votes
5 answers
8
Consider the following database relations containing the attributes Book_id Subject_Category_of_book Name_of_Author Nationality_of_Author With Book_id as the primary key. What is the highest normal form satisfied by this relation? Suppose the attributes Book_title and Author_address are ... is changed to {Name_of_Author, Book_title}, what will be the highest normal form satisfied by the relation?
22 votes
3 answers
9
Free disk space can be used to keep track of using a free list or a bit map. Disk addresses require $d$ bits. For a disk with $B$ blocks, $F$ of which are free, state the condition under which the free list uses less space than the bit map.
35 votes
4 answers
10
Four jobs are waiting to be run. Their expected run times are $6, 3, 5$ and $x.$ In what order should they be run to minimize the average response time? Write a concurrent program using $\text{par begin-par end}$ to represent the precedence graph shown below.
15 votes
1 answer
11
Let the attribute ‘$val$’ give the value of a binary number generated by $S$ in the following grammar: $S \rightarrow L.L \mid L$ $L \rightarrow LB \mid B$ $B \rightarrow 0 \mid 1$ For example, an input $101.101$ gives $S.val = 5.625$ Construct a syntax directed translation scheme using only synthesized attributes, to determine $S.val$.
18 votes
2 answers
12
An identifier in a programming language consists of up to six letters and digits of which the first character must be a letter. Derive a regular expression for the identifier. Build an $LL(1)$ parsing table for the language defined by the $LL(1)$ ... $X \rightarrow d \text{ semi } X \mid sY$ $Y \rightarrow \text{ semi } s Y \mid \epsilon$
17 votes
1 answer
13
Derive a recurrence relation for the size of the smallest AVL tree with height $h$. What is the size of the smallest AVL tree with height $8$?
18 votes
1 answer
14
Draw the binary tree with node labels $\text{a, b, c, d, e, f and g}$ for which the inorder and postorder traversals result in the following sequences: Inorder: $\text{a f b c d g e}$ Postorder: $\text{a f c g e d b}$
18 votes
5 answers
15
Let $p$ be a pointer as shown in the figure in a single linked list. What do the following assignment statements achieve? q: = p -> next p -> next:= q -> next q -> next:=(q -> next) -> next (p -> next) -> next:= q
28 votes
4 answers
16
For a set-associative Cache organization, the parameters are as follows: $\begin{array}{|c|l|} \hline \text {$t _c$} & \text{Cache Access Time }\\\hline \text{$ ... $n = k\times m$ is a non-zero integer and $1 < m \leq l$. Give the value of the hit ratio for $l = 1$.
3 votes
2 answers
17
Calculate the total time required to read 35 sectors on a 2-sided floppy disk. Assume that each track has 8 sectors and the track-to-track step time is 8 milliseconds. The first sector to be read is sector 3 on track 10. Assume that the diskette is soft sectored and the controller has a 1-sector buffer. The diskette spins at 300 RPM and initially, the head is on track 10.
21 votes
3 answers
18
Design a synchronous counter to go through the following states:$1, 4, 2, 3, 1, 4, 2, 3, 1, 4 \dots$
0 votes
0 answers
19
9 votes
3 answers
20
Let $G_1 = (N, T, P, S_1)$ be a CFG where, $N=\{S_1, A, B\},T=\{a, b\}$ and $P$ ... $5$ production rules. Is $L_2$ inherently ambiguous?
25 votes
1 answer
21
Let $M=(\{q_0, q_1\}, \{0, 1\}, \{z_0, X\}, \delta, q_0, z_0, \phi)$ be a Pushdown automation where $\delta$ is given by $\delta(q_0, 1, z_0) = \{(q_0, Xz_0)\}$ $\delta(q_0, \epsilon, z_0) = \{(q_0, \epsilon)\}$ ... $\delta(q_0, 0, z_0) = \{(q_0, z_0)\}$ What is the language accepted by this PDA by empty stack? Describe informally the working of the PDA
18 votes
2 answers
22
Let $(A, *)$ be a semigroup, Furthermore, for every $a$ and $b$ in $A$, if $a \neq b$, then $a*b \neq b*a$. Show that for every $a$ in $A$, $a*a=a$ Show that for every $a$, $b$ in $A$, $a*b*a=a$ Show that for every $a,b,c$ in $A$, $a*b*c=a*c$
23 votes
4 answers
23
Suppose $A = \{a, b, c, d\}$ and $\Pi_1$ is the following partition of A $\Pi_1 = \left\{\left\{a, b, c\right\}\left\{d\right\}\right\}$ List the ordered pairs of the equivalence relations induced by $\Pi_1$. Draw the graph of the above equivalence relation. Let ... $\left\langle\left\{\Pi_1, \Pi_2, \Pi_3, \Pi_4\right\}, \text{ refines } \right\rangle$.
17 votes
6 answers
24
Prove by induction that the expression for the number of diagonals in a polygon of $n$ sides is $\frac{n(n-3)}{2}$
2 votes
1 answer
25
Derive the expressions for the number of operations required to solve a system of linear equations in $n$ unknowns using the Gaussian Elimination Method. Assume that one operation refers to a multiplication followed by an addition.
8 votes
1 answer
26
Find the points of local maxima and minima, if any, of the following function defined in $0\leq x\leq 6$. $x^3-6x^2+9x+15$ Integrate $\int_{-\pi}^{\pi} x \cos x dx$
21 votes
3 answers
27
Suppose we have a database consisting of the following three relations. $\text{FREQUENTS (student, parlor)}$ giving the parlors each student visits. $\text{SERVES (parlor, ice-cream)}$ ... parlor) Express the following in SQL: Print the students that frequent at least one parlor that serves some ice-cream that they like.
22 votes
2 answers
28
Consider the grammar S $\rightarrow Aa \mid b$ A $\rightarrow Ac \mid Sd \mid \epsilon$ Construct an equivalent grammar with no left recursion and with minimum number of production rules.
20 votes
2 answers
29
The implication gate, shown below has two inputs ($x \text{ and }y)$; the output is 1 except when $x =1 \text{ and } y=0\text{, realize }f=\bar{x}y+x\bar{y}$ using only four implication gates. Show that the implication gate is functionally complete.
26 votes
2 answers
30
Design a deterministic finite state automaton (using minimum number of states) that recognizes the following language: $L=\{w \in \{0, 1\}^* \mid w$ interpreted as binary number (ignoring the leading zeros) is divisible by five $\}.$