From be7302a45e659a768be47e8435f863e6f19597a2 Mon Sep 17 00:00:00 2001
From: Ummon <greg.burri@gmail.com>
Date: Fri, 8 Dec 2017 11:18:13 +0100
Subject: [PATCH] Replace map + sum by sumBy

---
 AdventOfCode2017/Day2.fs | 7 ++-----
 AdventOfCode2017/Day3.fs | 3 +--
 AdventOfCode2017/Day7.fs | 2 +-
 3 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/AdventOfCode2017/Day2.fs b/AdventOfCode2017/Day2.fs
index c92fe54..bd91ef4 100644
--- a/AdventOfCode2017/Day2.fs
+++ b/AdventOfCode2017/Day2.fs
@@ -7,13 +7,11 @@ let parseInput (str : string) : int[][] =
     |> Array.map (fun line -> line.Split ([| ' '; '\t' |], StringSplitOptions.RemoveEmptyEntries) |> Array.map int)
 
 let checksum1 (a : int[][]) =
-    a
-    |> Array.map (fun ns -> Array.max ns - Array.min ns)
-    |> Array.sum
+    a |> Array.sumBy (fun ns -> Array.max ns - Array.min ns)
 
 let checksum2 (a : int[][]) =
     a
-    |> Array.map (
+    |> Array.sumBy (
         fun ns ->
             seq {
                 for a in ns do
@@ -21,4 +19,3 @@ let checksum2 (a : int[][]) =
                         if a <> b && a % b = 0 then yield a / b
             } |> Seq.head
     )
-    |> Array.sum
diff --git a/AdventOfCode2017/Day3.fs b/AdventOfCode2017/Day3.fs
index 3342111..71e57b6 100644
--- a/AdventOfCode2017/Day3.fs
+++ b/AdventOfCode2017/Day3.fs
@@ -21,8 +21,7 @@ let spiralAdjacentSumBiggerThan (n : int) =
     let neighborsSum (dic : Map<int * int, int>) (pos : int * int) =
         let x, y = pos
         [ for dx in -1 .. 1 do for dy in -1 .. 1 -> x + dx, y + dy ]
-        |> List.map (fun (x, y) -> match dic |> Map.tryFind (x, y) with Some v -> v | None -> 0)
-        |> List.sum
+        |> List.sumBy (fun (x, y) -> match dic |> Map.tryFind (x, y) with Some v -> v | None -> 0)
 
     spiral
     |> Seq.skip 1
diff --git a/AdventOfCode2017/Day7.fs b/AdventOfCode2017/Day7.fs
index 459f563..6f312f7 100644
--- a/AdventOfCode2017/Day7.fs
+++ b/AdventOfCode2017/Day7.fs
@@ -37,7 +37,7 @@ let buildTower (input : Input) : Tower =
 // Returns the tower and its corrected weight.
 let rec findUnbalanced (tower : Tower) : (Tower * int) option =
     let rec weight tower =
-        tower.Weight + (tower.Above |> Seq.map weight |> Seq.sum)
+        tower.Weight + (tower.Above |> Seq.sumBy weight)
 
     match tower.Above |> List.ofSeq |> List.groupBy weight |> List.sortBy (snd >> List.length) with
     | [ w1, [ unbalanced ]; w2, _ ] ->
-- 
2.45.2