Does anyone know the name of the following problem?

At a given day a number of $N$ salesmen (from the same company) are randomly scattered in a landscape with $M$ cities. At the next day as many cities as possible should have a salesman visiting, no two salesmen going to the same city. To what city $c_j$ should each salesman $s_i$ go to, in order to minimize the total distance travelled for all salesmen.

Note that if $M$ is less than $N$ some salesmen should stay on place and not go anywhere. We also assume that each salesmen can reach each city in the given time.

I would also be thankful for any pointer to algorithms solving the problem!

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I don't understand "as many cities as possible": you can always visit N cities, if there's no constraint on the total distance covered by all salesmen (or by a single salesman). – gd1 Jan 15 '13 at 16:11
Thanks, @Rahul, for the link (and answer!). I "jumped the gun"! – amWhy Jan 15 '13 at 16:14
I just meant that if there are more cities than salesmen, all cities would not have a salesman visiting. – Simon Jan 15 '13 at 16:24
Thank you Rahul! – Simon Jan 15 '13 at 16:30