Bit of work on day19

2021/nim/day19.nim

@@ -0,0 +1,202 @@
+import ./common, std/[sequtils, algorithm, sugar, sets, strformat, strutils, tables, options, json, hashes]
+
+type
+  Vec3 = array[3, int]
+  BeaconPositions = seq[Vec3]
+  Sensors = seq[BeaconPositions]
+  Vec3Pair = array[2, Vec3]
+  DumbDistTable = TableRef[int, Vec3Pair]
+
+proc dumbDist(a: Vec3, b: Vec3): int =
+  result = abs(a[0]-b[0]) + abs(a[1]-b[1]) + abs(a[2]-b[2])
+  # echo &"dumbDist: {result} from {a} to {b}"
+
+proc parse(s: string): Vec3 =
+  let l = s.split(",", 3).map parseInt
+  [l[0], l[1], l[2]]
+
+proc parse(l: openArray[string]): Sensors =
+  var sb: seq[Vec3] = @[]
+  for line in l:
+    if line == "":
+      result.add sb
+      continue
+    elif line[0] == '-' and line[1] == '-':
+      sb = @[]
+    else: sb.add line.parse
+  result.add sb
+
+proc p1(input: Sensors): uint64 =
+  var sensorsDumbDistTable = newTable[int, DumbDistTable]()
+  for i,s in input.pairs:
+    echo s
+    var dumbDistTable: DumbDistTable = newTable[int, Vec3Pair]()
+    for pair in product([s, s]):
+      if pair[0] == pair[1]: continue
+      dumbDistTable[dumbDist(pair[0], pair[1])] = [pair[0], pair[1]]
+    sensorsDumbDistTable[i] = dumbDistTable
+  var sensorMatches = newTable[int, int]()
+  for s1, ddt1 in sensorsDumbDistTable:
+    var maxMatches = 0
+    let kkeys = ddt1.keys.toSeq.sorted
+    echo &"Sorted {kkeys.len} Keys for Sensor {s1}: {kkeys}"
+    for s2, ddt2 in sensorsDumbDistTable:
+      if s1 == s2: continue
+      var ddMatches: seq[int] = @[]
+      for dd, vs in ddt1:
+        if ddt2.hasKey(dd): ddMatches.add dd
+      if ddMatches.len > maxMatches:
+        maxMatches = ddMatches.len
+        sensorMatches[s1] = s2
+      echo &"{s1} and {s2} have {ddMatches.len} dd matches: {ddMatches}"
+  # TODO once we have a solid guess of which sensors overlap using the dumbDist
+  # method, we'll need to actual math (probably?) to figure out how figure out
+  # the relative translation and rotation of the overlapping sensor using the
+  # matched points. once we can do that, we can "correct" the points from each
+  # sensor's beacons and remove overlapping onces.
+  # barring "actual math", I hate to imagine that this ends with brute-forcing
+  echo sensorMatches
+  0
+
+proc p2(input: Sensors): uint64 =
+  0'u64
+
+const input = """
+--- scanner 0 ---
+404,-588,-901
+528,-643,409
+-838,591,734
+390,-675,-793
+-537,-823,-458
+-485,-357,347
+-345,-311,381
+-661,-816,-575
+-876,649,763
+-618,-824,-621
+553,345,-567
+474,580,667
+-447,-329,318
+-584,868,-557
+544,-627,-890
+564,392,-477
+455,729,728
+-892,524,684
+-689,845,-530
+423,-701,434
+7,-33,-71
+630,319,-379
+443,580,662
+-789,900,-551
+459,-707,401
+
+--- scanner 1 ---
+686,422,578
+605,423,415
+515,917,-361
+-336,658,858
+95,138,22
+-476,619,847
+-340,-569,-846
+567,-361,727
+-460,603,-452
+669,-402,600
+729,430,532
+-500,-761,534
+-322,571,750
+-466,-666,-811
+-429,-592,574
+-355,545,-477
+703,-491,-529
+-328,-685,520
+413,935,-424
+-391,539,-444
+586,-435,557
+-364,-763,-893
+807,-499,-711
+755,-354,-619
+553,889,-390
+
+--- scanner 2 ---
+649,640,665
+682,-795,504
+-784,533,-524
+-644,584,-595
+-588,-843,648
+-30,6,44
+-674,560,763
+500,723,-460
+609,671,-379
+-555,-800,653
+-675,-892,-343
+697,-426,-610
+578,704,681
+493,664,-388
+-671,-858,530
+-667,343,800
+571,-461,-707
+-138,-166,112
+-889,563,-600
+646,-828,498
+640,759,510
+-630,509,768
+-681,-892,-333
+673,-379,-804
+-742,-814,-386
+577,-820,562
+
+--- scanner 3 ---
+-589,542,597
+605,-692,669
+-500,565,-823
+-660,373,557
+-458,-679,-417
+-488,449,543
+-626,468,-788
+338,-750,-386
+528,-832,-391
+562,-778,733
+-938,-730,414
+543,643,-506
+-524,371,-870
+407,773,750
+-104,29,83
+378,-903,-323
+-778,-728,485
+426,699,580
+-438,-605,-362
+-469,-447,-387
+509,732,623
+647,635,-688
+-868,-804,481
+614,-800,639
+595,780,-596
+
+--- scanner 4 ---
+727,592,562
+-293,-554,779
+441,611,-461
+-714,465,-776
+-743,427,-804
+-660,-479,-426
+832,-632,460
+927,-485,-438
+408,393,-506
+466,436,-512
+110,16,151
+-258,-428,682
+-393,719,612
+-211,-452,876
+808,-476,-593
+-575,615,604
+-485,667,467
+-680,325,-822
+-627,-443,-432
+872,-547,-609
+833,512,582
+807,604,487
+839,-516,451
+891,-625,532
+-652,-548,-490
+30,-46,-14
+""".strip().split('\n').parse
+doDayX 19, (n: int) => n.loadInput.parse, p1, p2, (input, 79'u64, 0'u64)