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Stacks exam tips
Study Stacks with curriculum-aligned Exam Tips resources, practice links, and exam-focused support.
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exam tips
Resource type
Topic
Stacks
AqaA LevelComputer ScienceFundamentals of data structures
Exam tips
Track the top after every operation
When tracing a sequence, record the stack from bottom to top after each push and pop, and do not alter it after a peek.
This makes it easier to identify the correct top value and prevents peek from being incorrectly treated as a removal operation.