Henry Ernest Dudeney/Puzzles and Curious Problems/261 - The Twenty-Two Bridges/Solution

by : $261$

 * The Twenty-Two Bridges

Solution
$C$ and $L$.

Proof
Each department has an even number of bridges leading from it, except $C$ and $L$, which have $3$.

The underlying graph of this map is therefore traversable.

From Characteristics of Traversable Graph it follows that $C$ and $L$ are the start and end points.

Hence, for example:


 * $C, G, F, C, B, A, D, H, E, I, H, J, K, L, M, G, I, F, B, E, F, I, L$