# 99 Elm Problems/Problem 91

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Find a path for for a chess knight on an NxN chessboard such that it visits every square exactly once? A set of solutions is given on the The_Knights_Tour page. Hints: Represent the squares by pairs of their coordinates of the form X/Y, where both X and Y are integers between 1 and N. (Note that '/' is just a convenient functor, not division!) Define the relation jump(N,X/Y,U/V) to express the fact that a knight can jump from X/Y to U/V on a NxN chessboard. And finally, represent the solution of our problem as a list of N*N knight positions (the knight's tour).

**# # # THIS IS A STUB # # #**

Example in Elm:

```
import Html exposing (text)
import List
f : Int -> Int
-- your implementation goes here
main = text (toString (f 0))
```

Result:

```
4
```