Add graphing library

flake.nix

@@ -45,6 +45,10 @@
             aeson
             random
             neat-interpolation
+
+            # graphing libraries!
+            Chart
+            Chart-cairo
           ]
         );
       in

src/projectEuler/question9.hs

@@ -1,3 +1,5 @@
+import           Graphics.Rendering.Chart.Backend.Cairo
+import           Graphics.Rendering.Chart.Easy
 {-
 Special Pythagorean Triplet
 Problem 9