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pp:l09 [2020/04/25 19:25] pdmatei |
pp:l09 [2020/04/25 19:31] (current) pdmatei |
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| - | 11. Define a function which computes, for a given position, the list of valid //next positions// (a valid position is one that is on the map, and it is not a //wall//, i.e. a ''#''). | + | 11. Define a function which computes, for a given position, the list of valid //next positions// (a valid position is one that is on the map, and it is not a //wall//, i.e. a ''#''). Hint, use the list ''[(x-1,y-1),(x-1,y),(x-1,y+1),(x,y-1),(x,y+1),(x+1,y-1),(x+1,y),(x+1,y+1)]''. |
| + | |||
| + | 12. Implement the type ''Tree a'' of trees with arbitrary number of children nodes. | ||
| + | |||
| + | 13. Enrol ''Tree'' in class ''Functor'' (see classes), and define the function ''fmap''. | ||
| + | |||
| + | 14. Write a function which takes a (possibly infinite) tree and returns the sub-tree where each branch is of length at most ''k'': | ||
| + | <code haskell> | ||
| + | take_t :: Integer -> Tree a -> Tree a | ||
| + | </code> | ||
| + | |||
| + | 15. Implement the infinite tree of valid positions, starting from an initial one. In this tree, paths represent trails exploring the map. | ||
| + | <code haskell> | ||
| + | make_st_tree :: Map -> State -> Tree State | ||
| + | </code> | ||
| + | 16. Implement the function ''toMap'' which //draws// a position on the map (using the character ''.''). | ||
| + | <code haskell> | ||
| + | toMap :: State -> Map -> Map | ||
| + | </code> | ||
| + | |||
| + | 17. Implement the tree of possible //trails// through the map: | ||
| + | <code haskell> | ||
| + | make_map_tree :: Map -> State -> Tree Map | ||
| + | </code> | ||