Q.1
Which of the following pairs have DIFFERENT expressive power?
  • Deterministic finite automata (DFA) and Non-Deterministic finite automata(NFA)
  • Deterministic push down automata (DPDA) and Non-deterministic pushdown automata
  • Deterministic single-tape Turing machine and Non-deterministic single-tape Turing Machine
  • Single-tape Turing machine and multi-tape Turing machine
Q.2
In multi-programmed systems, it is advantageous if some programs such as editors and compilers can be shared by several users. Which of the following must be true of multi-programmed systems in order that a single copy of a program can be shared by several users? I. The program is a macro II. The program is recursive III.The program is reentrant
  • I only
  • II only
  • Ill only
  • I, II and III
Q.3
Consider the following expressionu*v+a-b*c Which one of the following corresponds to a static single assignment from the above expressions
  • x1 = a - b y1 = p * c x2 = u * v y2 = p + q
  • x 1 = a - b y1 = x2 * c x3 = u * v y2 = x4 + y3
  • x1 = a - b y2 = x1 * c x2 = u * v y3 = x2 + y2
  • p = a - b q = p * c p = u * v q = p + q
Q.4
Which of the following macros can put a micro assembler into an infinite loop?(i) .MACRO M1 X.IF EQ, X ;if X=0 thenM1 X + 1.ENDC.IF NE X ;IF X≠0 then.WORD X ;address (X) is storedhere.ENDC.ENDM(ii).MACRO M2 X.IF EQ XM2 X.ENDC.IF NE, X.WORD X+1.ENDC.ENDM
  • (ii) only
  • (i) only
  • Both (i) and (ii)
  • None of the above
Q.5
The expression (a*b)* c op........ where 'op' is one of '+', '*' and '↑' (exponentiation) can be evaluated on a CPU with a single register without storing the value of (a * b) if
  • ‘op’ is ‘+’ or ‘*’
  • 'op’ is ‘↑’ or ‘*’
  • 'op’ is ‘↑’ or ‘+’
  • not possible to evaluate without storing
Q.6
A language L allows declaration of arrays whose sizes are not known during compilation. It is required to make efficient use of memory. Which of the following is true?
  • A compiler using static memory allocation can be written for L
  • A compiler cannot be written for L, an interpreter must be used
  • A compiler using dynamic memory allocation can be written for L
  • None of the above
Q.7
A linker reads four modules whose lengths areandwords respectively. If they are loaded in that order, what are the relocation constants?
  • 0, 200, 500, 600
  • 0, 200, 1000, 1600
  • 200, 500, 600, 800
  • 200, 700, 1300, 2100
Q.8
Consider the following C code segment.for (i =i
  • The code contains loop invariant computation
  • There is scope of common sub-expression elimination in this code
  • There is scope of strength reduction in this code
  • There is scope of dead code elimination in this code
Q.9
Incremental-Compiler is a compiler
  • which is written in a language that is different from the source language
  • compiles the whole source code to generate object code afresh
  • compiles only those portion of source code that have been modifie
  • that runs on one machine but produces object code for another machine
Q.10
Shift-Reduce parsers perform the following:
  • Shift step that advances in the input stream by K(K > 1) symbols and Reduce step that applies a completed grammar rule to some recent parse trees, joining them together as one tree with a new root symbol.
  • Shift step that advances in the input stream by one symbol and Reduce step that applies a completed grammar rule to some recent parse trees, joining them together as one tree with a new root symbol.
  • Shift step that advances in the input stream by K(K = 2) symbols and Reduce step that applies a completed grammar rule to form a single tree
  • Shift step that does not advance in the input stream and Reduce step that applies a completed grammar rule to form a single tre
Q.11
Which is True about SR and RR-conflict:
  • If there is no SR-conflict in CLR(1) then definitely there will be no SR-conflict in LALR(1).
  • RR-conflict might occur if lookahead for final items(reduce-moves) is sam
  • Known that CLR(1) has no RR-conflict, still RR-conflict might occur in LALR(1).
  • All of the abov
Q.12
Consider the following grammars(S:A --> aBCDB --> bc|cC --> d|∈D -> b(S:A --> aBCDB --> bc|∈C --> d|cD -> b(S:A --> aBCDB --> bc|∈C --> d|∈D -> b(S:A --> aBCDB --> bc|cC --> d|cD -> bWhich of the following grammar has same follow set for variable B?
  • Only (S1), (S2) and (S3), (S4)
  • Only (S1), (S3) and (S2), (S4)
  • Only (S2), (S3) and (S1), (S4)
  • None of the above
Q.13
The grammar whose productions are → if id then → if id then else → id := idis ambiguous becausea) the sentence if a then if b then c:= d has two parse treesb) the left most and right most derivations of the sentence if a then if b then c:= d give rise to different parse treesc) the sentence if a then if b then c:= d else c:= f has more than two parse treesd) the sentence if a then if b then c:= d else c:= f has two parse trees
  • a
  • b
  • c
  • d
Q.14
Which of the following is essential for converting an infix expression to the postfix from efficiently?
  • An operator stack
  • An operand stack
  • An operand stack and an operator stack
  • A parse tree
Q.15
Consider the following expression grammar. The seman-tic rules for expressioncalculation are stated next to each grammar production.E → number E.val = number. val | E '+' E E(1).val = E(2).val + E(3).val | E '×' E E(1).val = E(2).val × E(3).valThe above grammar and the semantic rules are fed to a yacc tool (which is an LALR (1)parser generator) for parsing and evaluating arithmetic expressions. Which one of thefollowing is true about the action of yacc for the given grammar?
  • It detects recursion and eliminates recursion
  • It detects reduce-reduce conflict, and resolves
  • It detects shift-reduce conflict, and resolves the conflict in favor of a shift over a reduce action
  • It detects shift-reduce conflict, and resolves the conflict in favor of a reduce over a shift action
Q.16
Consider the grammar S → (S) | a Let the number of states in SLR(1), LR(and LALR(parsers for the grammar be nn2 and n3 respectively. The following relationship holds good
  • n1 < n2 < n3
  • n1 = n3 < n2
  • n1 = n2 = n3
  • n1 ≥ n3 ≥ n2
Q.17
Debugger is a program that
  • allows to examine and modify the contents of registers
  • does not allow execution of a segment of program
  • allows to set breakpoints, execute a segment of program and display contents of register
  • All of the above
Q.18
From the given data below : a b b a a b b a a b which one of the following is not aword in the dictionary created by LZ-coding (the initial words are a, b)?
  • a b
  • b b
  • b a
  • b a a b
Q.19
Consider the following statements related to compiler construction : I. Lexical Analysis is specified by context-free grammars and implemented by pushdown automata. II. Syntax Analysis is specified by regular expressions and implemented by finite-state machine. Which of the above statement(s) is/are correct?
  • Only I
  • Only II
  • Both I and II
  • Neither I nor II
Q.20
Consider the following statements:(I) The output of a lexical analyzer is groups of characters.(II) Total number of tokens in printf("i=%d, &i=%x", i, &i); are 11.(III) Symbol table can be implementation by using array and hash table but not tree.Which of the following statement(s) is/are correct?
  • Only (I)
  • Only (II) and (III)
  • All (I), (II), and (III)
  • None of these
0 h : 0 m : 1 s