GATE CSE 2015 SET-2
Q31.
Consider the sequence of machine instructions given below: MUL R5, R0, R1 DIV R6, R2, R3 ADD R7, R5, R6 SUB R8, R7, R4 In the above sequence, R0 to R8 are general purpose registers. In the instructions shown, the first register stores the result of the operation performed on the second and the third registers. This sequence of instructions is to be executed in a pipelined instruction processor with the following 4 stages: (1) Instruction Fetch and Decode (IF), (2) Operand Fetch (OF), (3) Perform Operation (PO) and (4) Write back the result (WB). The IF, OF and WB stages take 1 clock cycle each for any instruction. The PO stage takes 1 clock cycle for ADD or SUB instruction, 3 clock cycles for MUL instruction and 5 clock cycles for DIV instruction. The pipelined processor uses operand forwarding from the PO stage to the OF stage. The number of clock cycles taken for the execution of the above sequence of instructions is ___________.Q32.
The secant method is used to find the root of an equation f(x)=0. It is started from two distinct estimates x_{a} and x_{b} for the root. It is an iterative procedure involving linear interpolation to a root. The iteration stops if f(x_{b}) is very small and then x_{b} is the solution. The procedure is given below. Observe that there is an expression which is missing and is marked by ?. Which is the suitable expression that is to be put in place of ? so that it follows all steps of the secant method?Q33.
Consider the following routing table at an IP router: For each IP address in Group I identify the correct choice of the next hop from Group II using the entries from the routing table above.Q35.
Consider the following two statements. S1: If a candidate is known to be corrupt, then he will not be elected S2: If a candidate is kind, he will be elected Which one of the following statements follows from S1 and S2 as per sound inference rules of logic?Q36.
Which of the following languages is/are regular? L_{1}:\{wxw^{R}|w,x \in \{a,b\}^{*} \; and \; |w|,|x| \gt 0 \}, w^{R} is the reverse of string w L_{2}:\{a^{n}b^{m}|m\neq n \; and \; m,n\geq 0\} L_{3}:\{a^{p}b^{q}c^{r}|p,q,r\geq 0\}Q37.
Consider two relations R1(A,B) with the tuples (1,5), (3,7) and R2(A,C) = (1,7), (4,9). Assume that R(A,B,C) is the full natural outer join of R1 and R2. Consider the following tuples of the form (A,B,C): a = (1,5,null), b = (1,null,7), c = (3, null, 9), d = (4,7,null), e = (1,5,7), f = (3,7,null), g = (4,null,9). Which one of the following statements is correct?Q38.
Consider the alphabet \Sigma={0, 1}, the null/empty string \lambda and the sets of strings X_{0}, X_{1}, \; and \; X_{2} generated by the corresponding non-terminals of a regular grammar. X_{0}, X_{1}, \; and \; X_{2} are related as follows. X_{0}=1X_{1} X_{1},=0X_{1}+1 X_{2} X_{2}=0X_{1}+ \{\lambda\} Which one of the following choices precisely represents the strings in X_{0}?Q39.
Consider a typical disk that rotates at 15000 rotations per minute (RPM) and has a transfer rate of 50x10^{6} bytes/sec. If the average seek time of the disk is twice the average rotational delay and the controller's transfer time is 10 times the disk transfer time, the average time (in milliseconds) to read or write a 512-byte sector of the disk is ______.Q40.
Let R be the relation on the set of positive integers such that aRb if and only if a and b are distinct and have a common divisor other than 1. Which one of the following statements about R is true?