How do I set up Soft Selection in 3Ds Max like Ring?

I'm creating a model of the ship from TES III: Morrowind (the same ship from which the new game begins). I need to build a cabin. From above it looks like this:

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That is, by the end it narrows. The only thing that came to my mind was how to do it - Soft Selection. The problem is that it highlights everything around the highlighted point/rib/landfill:

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And I need the selection to be like this:

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That is, about like a Ring, but one way. The question is how to set up Soft Selection in this way, or if it is not possible, how it can be implemented in another way (not manually).