Solve AOC day 9

projects/aoc/src/year2020/Solutions.kiss

@@ -89,5 +89,14 @@
         (bootCode.setBreakHandler (lambda [:BootCodeFix bootCodeFork] (when (= bootCodeFork.instructionPointer (bootCodeFork.instructionCount)) (print .accumulator (the BootCodeFix bootCodeFork)))))
         (bootCode.addBreakPoint (bootCode.instructionCount))
         (bootCode.run))
+    
+    // Day 9
+    (assert (= 127 (XMAS.firstOffender 5
+        [35 20 15 25 47 40 62 55 65 95 102 117 150 182 127 219 299 277 309 576])))
+    (assert (= 133015568 (XMAS.firstOffender 25 (Util.readInts "src/year2020/inputs/day9.txt"))))
+    (assert (= "[15,25,47,40]" (.toString (SummingTuples.contiguousSumTuple 127
+        [35 20 15 25 47 40 62 55 65 95 102 117 150 182 127 219 299 277 309 576]))))
+    (let [tuple (SummingTuples.contiguousSumTuple 133015568 (Util.readInts "src/year2020/inputs/day9.txt"))]
+        (assert (= 16107959 (+ (apply min tuple) (apply max tuple)))))
     )
     

projects/aoc/src/year2020/SummingTuples.kiss

@@ -14,4 +14,16 @@
                 pairThatSatisfies (pairWithSum requiredForTrio numbers)]
             (when pairThatSatisfies
                 (return [number (nth pairThatSatisfies 0) (nth pairThatSatisfies 1)]))))
+    null)
+
+(defun contiguousSumTuple [sum :kiss.List<Int> numbers]
+    (doFor i (range numbers.length)
+        (deflocal &mut testSum (nth numbers i))
+        (doFor j (range (+ i 1) numbers.length)
+            (set testSum (+ testSum (nth numbers j)))
+            (cond 
+                ((= testSum sum)
+                    (return (numbers.slice i (+ j 1))))
+                ((> testSum sum)
+                    (break)))))
     null)

projects/aoc/src/year2020/XMAS.hx

@@ -0,0 +1,7 @@
+package year2020;
+
+import kiss.Prelude;
+import year2020.SummingTuples;
+
+@:build(kiss.Kiss.build("src/year2020/XMAS.kiss"))
+class XMAS {}

projects/aoc/src/year2020/XMAS.kiss

@@ -0,0 +1,5 @@
+(defun firstOffender [preambleLength :kiss.List<Int> input]
+    (doFor idx (range preambleLength input.length)
+        (unless (SummingTuples.pairWithSum (nth input idx) (input.slice (- idx preambleLength) idx))
+            (return (nth input idx))))
+    (print null))