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Which one of the following is a top-down parser?

1. Recursive descent parser.
2. Operator precedence parser.
3. An LR(k) parser.
4. An LALR(k) parser.

Correct answer: Recursive descent parser.

Solution

Recursive descent parsing is a classic top-down parsing technique. The other listed parsers are bottom-up or shift-reduce based methods.

Related GATE Technical questions

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