1
GATE CSE 2021 Set 1
Numerical
+2
-0.67

Consider the following C code segment:

a = b + c;

e = a + 1;

d = b + c;

f = d + 1;

g = e + f;

In a compiler, this code segment is represented internally as a directed acyclic graph (DAG). The number of nodes of nodes in the DAG is ______

2
GATE CSE 2018
+2
-0.6
Which one of the following statements is FALSE?
A
Context-free grammar can be used to specify both lexical and syntax rules.
B
Type checking is done before parsing.
C
High-level language programs can be translated to different Intermediate Representations.
D
Arguments to a function can be passed using the program stack.
3
GATE CSE 2018
+2
-0.6
A lexical analyzer uses the following patterns to recognize three tokens $${T_1},{T_2},$$ and $${T_3}$$ over the alphabet $$\left\{ {a,b,c} \right\}.$$

\eqalign{ & {T_1}:\,\,\,a?{\left( {b|c} \right)^ * }a \cr & {T_2}:\,\,\,b?{\left( {a|c} \right)^ * }b \cr & {T_3}:\,\,\,c?{\left( {b|a} \right)^ * }c \cr}

Note that $$'x?'$$ means $$0$$ or $$1$$ occurrence of the symbol $$x.$$ Note also that the analyzer outputs the token that matches the longest possible prefix.

If the string $$bbaacabc$$ is processed by the analyzer, which one of the following is the sequence of tokens it outputs?

A
$${T_1}{T_2}{T_3}$$
B
$${T_1}{T_1}{T_3}$$
C
$${T_2}{T_1}{T_3}$$
D
$${T_3}{T_3}$$
4
GATE CSE 2016 Set 2
+2
-0.6
Which one of the following grammars is free from $$left$$ $$recursion$$?
A
\eqalign{ & S\,\, \to \,\,AB \cr & A\,\, \to \,\,Aa\,\,|\,\,b \cr & B \to c \cr}
B
\eqalign{ & S\,\, \to \,\,AB\,\,|\,\,Bb\,\,|\,\,c \cr & A\,\, \to \,\,Bd\,\,|\,\,\varepsilon \cr & B \to e \cr}
C
\eqalign{ & S\,\, \to \,\,Aa\,\,|\,\,B\,\,|\,\, \cr & A\,\, \to \,\,Bd\,\,|\,\,Sc\,\,|\,\,\varepsilon \cr & B \to d \cr}
D
\eqalign{ & S\,\, \to \,\,Aa\,\,|\,\,Bb\,\,|\,\,c \cr & A\,\, \to \,\,Bd\,\,|\,\,\varepsilon \cr & B \to Ae\,\,|\,\,\varepsilon \cr}
GATE CSE Subjects
EXAM MAP
Medical
NEET