GATE CS 2015 Set 2 — Question 27

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MCQ+1 / -0.33EasyLexer Construction (DFA/NFA)Lexical AnalysisCompiler DesignParse TreesSyntax AnalysisRegister AllocationCode OptimizationExpression EvaluationStacks & QueuesProgramming & Data Structures

Compiler Design → Code Optimization → Expression Evaluation

Last updated 5 September 2026

Question

Match the following: Group I Group II P. Lexical analysis 1. Graph coloring Q. Parsing 2. DFA minimization R. Register allocation 3. Post-order traversal S. Expression evaluation 4. Production tree

Group I	Group II
P. Lexical analysis	1. Graph coloring
Q. Parsing	2. DFA minimization
R. Register allocation	3. Post-order traversal
S. Expression evaluation	4. Production tree

Correct answer (C) P-2, Q-4, R-1, S-3 Solution Lexical analysis (P) uses Finite Automata, so it relates to DFA minimization (2) . Parsing (Q) constructs a parse tree or Production tree (4) . Register allocation (R) is often modeled as a Graph coloring (1) problem (interference graph). Expression evaluation (S) is typically done using a Post-order traversal (3) of the expression tree. Matching: P-2, Q-4, R-1, S-3. Turn this into a strength. Explore AI-powered practice and doubt support with Success Tracker.

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Correct answer (C) P-2, Q-4, R-1, S-3 Solution Lexical analysis (P) uses Finite Automata, so it relates to DFA minimization (2) . Parsing (Q) constructs a parse tree or Production tree (4) . Register allocation (R) is often modeled as a Graph coloring (1) problem (interference graph). Expression evaluation (S) is typically done using a Post-order traversal (3) of the expression tree. Matching: P-2, Q-4, R-1, S-3.

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GATE CS 2015 Set 2 — Question 27

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