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Video transcript

in the rest of this lesson we're gonna look at a few other counting problems that come up when you try to make a large crowd of robots from a small bin of parts we're gonna be building up to a really powerful formula that you can think of as a counting tool to start let's imagine snake-like robots let's call them snake BOTS they are built as a sequence of segments where every segment must be used exactly once for instance if I'm building a three segment snake body I might assemble the segments this way or I could do it this way we'd again like to know how many of these snake BOTS can I build remember you have to account for every possibility in the next exercise you're going to be asked to build all possible snake BOTS of length one through four go get them