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Computer Science interview
Use abstraction, decomposition and algorithms to formalise a problem.
One thinking framework
Use the same five steps for the exercises below. Familiarise yourself once, then focus on explaining your reasoning.
Five steps for your reasoning
1
Define variables, assumptions and a model
State what you are studying and what you will temporarily ignore.
2
Explain your choice of method
Connect your formula, theorem or comparison to the problem.
3
Explain each step as you calculate
Explain relationships, substitutions and intermediate conclusions.
4
Check units, scale and plausibility
Check signs, ranges, dimensions and possible sources of error.
5
Adapt to hints and changes
Identify which assumption changes and revise your approach.
1
You need to find a word in a dictionary of 1000 pages sorted alphabetically. Describe as fast a strategy as possible, and estimate the number of page turns in the worst case.
2
How do you determine whether a very large list contains any duplicate elements? How much time and memory does your method require?