Bridge and torch
Definition · Level 11 · Interview practice
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Four people taking 1, 2, 5 and 10 minutes cross two at a time with one light: 17 minutes — send the two slowest together and use the two fastest as shuttles.
Example
1+2 (2), 1 back (1), 5+10 (10), 2 back (2), 1+2 (2) = 17.
Where Tradecraft teaches it
Level 11 · Interview practice, in the lesson “Brainteasers: the classic set”: Crisp answers and one-line reasons for the puzzles interviewers ask most.
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