Add correct day3pt1

diff --git a/resources/day03 b/resources/day03
new file mode 100644 (file)
index 0000000..07b6fd9
--- /dev/null
+++ b/resources/day03
@@ -0,0 +1,2 @@
+R1005,U370,L335,D670,R236,D634,L914,U15,R292,D695,L345,D183,R655,U438,R203,U551,L540,U51,R834,D563,L882,D605,L832,U663,R899,D775,L740,U764,L810,U442,R379,D951,L821,D703,R526,D624,L100,D796,R375,U129,L957,D41,R361,D504,R358,D320,L392,D842,R509,D612,L92,U788,L361,D757,R428,U257,L663,U956,L748,U938,R588,D942,R819,D732,R562,D331,L164,U801,R872,U872,L909,U260,R899,D278,R822,U968,L937,D594,L786,D34,R102,D650,R920,D539,R925,U436,R347,U686,L596,D608,R730,U5,R462,U831,R277,U411,R730,D828,L169,D276,L669,U167,R55,D879,L329,U258,R585,D134,R977,D609,L126,U848,L601,U624,R577,D421,L880,D488,R505,U385,L103,D693,L110,D338,R809,D864,L80,U413,R412,D134,L519,D988,R83,U580,R593,U435,R843,D953,R11,D655,R569,D237,R987,U894,L445,U974,L746,U450,R99,U69,R84,U258,L248,D581,R215,U306,R480,U126,R275,D353,R493,D800,L386,D876,L957,D722,L967,D612,L716,D901,R394,U764,R274,D686,L746,D957,R747,U517,L575,D961,R842,D753,L345,D59,L215,U413,R610,D166,L646,U107,L926,D848,R445,U297,L376,U869,L345,D529,R620,D353,R682,D908,R378,D221,R64,D911,L245,D364,R123,D555,L928,U412,R771,D543,L97,D477,R500,D125,R578,U150,R291,D252,R948,D576,L838,D144,L289,D677,L307,U692,R802,D743,R57,U839,R896,D110,R34,D508,L595,U658,L769,U47,L292,U66,R217,D8,L835,D479,L71,D24,R429,U64,R305,D406,R23,U819,R478,D7,L561,D503,R349,U104,L749,D123,R548,D421,R336,D837,R464,D908,L94,U988,L137,D757,L42,U842,R260,D406,L31,U965,L178,U973,L29,U276,L887,U920,L133,U243,R537,U282,R194,D152,R693,D509,L771,D365,L319,D378,L61,D849,R379
+L998,U242,R333,U631,L507,U313,R286,U714,R709,U585,R393,D893,R404,D448,R882,U246,L190,U238,R672,D184,L275,D120,R352,D584,L626,U413,L288,D942,R770,D551,L926,D242,R568,U48,R108,D349,R750,D323,L529,D703,L672,U775,L700,D465,L528,D596,R990,U366,L747,D270,L723,D469,L548,D47,L873,D678,R782,D187,L397,U975,R967,D224,L295,D86,L159,U610,L767,U641,L885,D623,L160,D509,R517,D981,L376,D604,R251,D140,L938,D358,L984,U63,R513,D54,L718,U90,L343,D982,L575,D692,L508,D361,L297,D880,L46,D875,R40,D97,R819,U919,R319,U152,R161,U553,L388,D100,R481,U306,L201,U706,L173,D657,L632,D182,R477,D332,R678,D683,L983,D584,R941,U801,R485,D376,R218,D432,R780,D617,R560,D618,R466,U456,L952,D72,R339,U16,L543,U176,L423,D770,L714,U621,L850,U929,R132,D908,R993,U440,R539,U374,L945,D443,L326,D651,L269,U321,R925,D777,R431,U273,R811,D63,R683,D540,L3,D617,R359,U332,L736,D98,L859,D994,R131,U71,L156,D661,R879,D303,L581,U407,L166,U878,L831,D871,R953,D137,L903,U200,R34,D857,R448,D412,L311,D212,R527,D707,R641,D775,L987,D814,L38,D96,R647,U868,L98,U882,L838,D308,R840,U161,R83,U424,L420,U934,R353,D287,R559,D665,R695,D888,R859,U992,L283,D525,L449,U255,L889,D296,R72,D899,R316,D3,L308,D404,L356,D333,R645,U274,R336,U258,R599,U746,L142,U21,R301,D890,L290,D624,R565,U117,L927,U412,L687,U480,R674,U372,L382,D134,L372,D892,R307,U217,L20,D535,L876,D548,L19,U590,R906,D816,R465,U768,R882,U980,L557,D788,R645,U684,L255,D803,L374,U759,L693,D92,L256,U772,R591,D126,R57,U363,R347,U191,L760,U223,R591,D507,R232,U251,R471,D912,R227

diff --git a/src/adventofcode2019/day03.clj b/src/adventofcode2019/day03.clj
new file mode 100644 (file)
index 0000000..17564de
--- /dev/null
+++ b/src/adventofcode2019/day03.clj
@@ -0,0 +1,50 @@
+(ns adventofcode2019.day03
+    [:require [adventofcode2019.lib :refer :all]
+              [clojure.string :as str]
+              [clojure.set :as set]
+              [clojure.math.combinatorics :as combo]])
+
+(defn parse-input [input]
+  (map #(str/split % #",") (str/split-lines (str/trim (slurp input)))))
+
+(defn spec->op [spec]
+  (let [direction (first spec)
+        distance (parse-int (str/join (rest spec)))]
+    (case direction
+      \U (fn [[x y]] [x (+ y distance)])
+      \D (fn [[x y]] [x (- y distance)])
+      \R (fn [[x y]] [(+ x distance) y])
+      \L (fn [[x y]] [(- x distance) y]))))
+
+
+(defn ints-between [x y]
+  (cond 
+    (> x y) (range y (inc x))
+    (< x y) (range x (inc y))
+    :else [x]))
+
+(defn points-diff [pos-a pos-b]
+  (let [[a-x a-y] pos-a
+        [b-x b-y] pos-b]
+    (set (for [x (ints-between a-x b-x)
+               y (ints-between a-y b-y)]
+              [x y]))))
+
+(defn wire-spec->points [wire]
+  (let [wire-ops (map spec->op wire)
+        trace-reduction (fn [{:keys [pos points]} op]
+                            (let [new-pos (op pos)
+                                  new-points (points-diff pos new-pos)]
+                              {:pos new-pos :points (set/union points new-points)}))
+        trace (reduce trace-reduction {:pos [0 0], :points #{}} wire-ops)]
+    (:points trace)))
+
+(defn find-intersections [wires]
+  (let [wires-points (map wire-spec->points wires)]
+    (set/difference (apply set/intersection wires-points) #{[0 0]})))
+
+(defn day03 []
+  (let [wires (parse-input (input-file))
+        manhattan-distance (fn [[x y]] (+ (Math/abs x) (Math/abs y)))
+        intersections (find-intersections wires)] 
+    (println (apply min (map manhattan-distance intersections)))))