Problem #1 MEDIUM
The Bridge at Midnight
Google Amazon Logic
Problem Statement
Four travelers need to cross a rickety bridge at night. The bridge is in such poor condition that it can support at most two people at a time. Because it is pitch black, they must carry a single flashlight to guide their way. Every group crossing the bridge, whether one or two people, must travel at the speed of the slowest person.
The four travelers walk at different speeds: Alice takes 1 minute to cross, Bob takes 2 minutes, Charlie takes 5 minutes, and Daniel takes 10 minutes.
What is the absolute minimum time required for all four travelers to cross to the other side?
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