# Difference between revisions of "One-way roads"

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==Puzzle== | ==Puzzle== | ||

− | A county has < | + | A county has <m>n > 4</m> cities. Is it possible to connect some pairs of cities by one-way roads so that one can travel from every city to every other city using only one or two roads? If so, how? Note that for every pair of cities A and B, only one road connecting A with B is allowed; this road leads from A to B or from B to A, but not both ways. |

[[Category: Graph theory]] | [[Category: Graph theory]] | ||

[[Category: New]] | [[Category: New]] | ||

[[Category: Needs solution]] | [[Category: Needs solution]] |

## Current revision as of 19:11, 24 July 2017

Found this one on the SUNY Stony Brook Math Problem of the Month archives.

## Puzzle

A county has <m>n > 4</m> cities. Is it possible to connect some pairs of cities by one-way roads so that one can travel from every city to every other city using only one or two roads? If so, how? Note that for every pair of cities A and B, only one road connecting A with B is allowed; this road leads from A to B or from B to A, but not both ways.