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Context-free languages exam tips
Study Context-free languages with curriculum-aligned Exam Tips resources, practice links, and exam-focused support.
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exam tips
Resource type
Topic
Context-free languages
AqaA LevelComputer ScienceTheory of computation
Exam tips
Trace every alternative
When checking a string against BNF or a syntax diagram, follow the rules from the start symbol and consider each alternative and optional route.
A string is valid only if a complete derivation reaches the end while consuming the whole string.
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