diff --git a/src/projectEuler/question15.hs b/src/projectEuler/question15.hs
index 94d7c7d..4a9f5ed 100644
--- a/src/projectEuler/question15.hs
+++ b/src/projectEuler/question15.hs
@@ -14,10 +14,31 @@ main = print ans
 
 ans = 42
 
-limit = 20
-points = [(x,y) | x <- [1..limit], y <- [1..limit]]
+limit = 2
+points = [ (x,y)
+  | x <- [0..limit]
+  , y <- [0..limit]
+  ]
 
 data Direction = Right | Down
 
 move Right (x,y) = (x+1, y  )
 move Down  (x,y) = (x  , y+1)
+
+-- solve :: (Int, Int) -> [[(Int, Int)]]
+{-
+λ> [(0,0)]
+[(0,0)]
+λ> [(0,0),(1,0),(2,0),(2,1),(2,2)]
+[(0,0),(1,0),(2,0),(2,1),(2,2)]
+λ> [ [(0,0),(1,0),(2,0),(2,1),(2,2)], [(0,0),(1,0),(1,1),(2,1),(2,2)]]
+[[(0,0),(1,0),(2,0),(2,1),(2,2)],[(0,0),(1,0),(1,1),(2,1),(2,2)]]
+λ>
+-}
+
+data Tree a
+  = Leaf a
+  | Branch (Tree a) (Tree a)
+  deriving (Show)
+
+