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Problem #18 MEDIUM

The Bridge and Torch

Google Microsoft Lateral Thinking

Problem Statement

<p>Four people need to cross a bridge at night. They have one torch and the bridge can hold at most two people at once. They walk at different speeds: Person A takes 1 min, B takes 2 min, C takes 5 min, D takes 10 min. When two people cross together, they move at the slower person's speed. The torch must be carried across and back. What is the minimum time to get everyone across?</p><p></p>

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