From f1cb8ad58a58bcceb8afe1ce211828117e01c07e Mon Sep 17 00:00:00 2001
From: Julien Dessaux
Date: Thu, 8 Dec 2022 11:56:34 +0100
Subject: 2022-08 in zig

---
 2022/08-treetop-tree-house/example    |   5 ++
 2022/08-treetop-tree-house/first.zig  | 106 ++++++++++++++++++++++++++++++++++
 2022/08-treetop-tree-house/input      |  99 +++++++++++++++++++++++++++++++
 2022/08-treetop-tree-house/second.zig | 101 ++++++++++++++++++++++++++++++++
 4 files changed, 311 insertions(+)
 create mode 100644 2022/08-treetop-tree-house/example
 create mode 100644 2022/08-treetop-tree-house/first.zig
 create mode 100644 2022/08-treetop-tree-house/input
 create mode 100644 2022/08-treetop-tree-house/second.zig

(limited to '2022')

diff --git a/2022/08-treetop-tree-house/example b/2022/08-treetop-tree-house/example
new file mode 100644
index 0000000..16d6fbd
--- /dev/null
+++ b/2022/08-treetop-tree-house/example
@@ -0,0 +1,5 @@
+30373
+25512
+65332
+33549
+35390
diff --git a/2022/08-treetop-tree-house/first.zig b/2022/08-treetop-tree-house/first.zig
new file mode 100644
index 0000000..07db936
--- /dev/null
+++ b/2022/08-treetop-tree-house/first.zig
@@ -0,0 +1,106 @@
+const std = @import("std");
+
+const example = @embedFile("example");
+const input = @embedFile("input");
+
+pub fn main() anyerror!void {
+    var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
+    defer arena.deinit();
+    const allocator = arena.allocator();
+
+    try std.testing.expectEqual(try solve(example, allocator), 21);
+    const result = try solve(input, allocator);
+    try std.io.getStdOut().writer().print("{}\n", .{result});
+}
+
+fn solve(puzzle: []const u8, allocator: std.mem.Allocator) !u64 {
+    var it = std.mem.tokenize(u8, puzzle, "\n");
+    var heights = std.ArrayList(std.ArrayList(u8)).init(allocator);
+    var visibility = std.ArrayList(std.ArrayList(bool)).init(allocator);
+    // process input
+    var line = it.next() orelse unreachable;
+    const width = line.len;
+    while (true) {
+        var h = try heights.addOne();
+        var v = try visibility.addOne();
+        h.* = try std.ArrayList(u8).initCapacity(allocator, width);
+        v.* = try std.ArrayList(bool).initCapacity(allocator, width);
+        try h.*.writer().writeAll(line);
+        v.*.appendAssumeCapacity(true);
+        var i: usize = 1;
+        while (i < width - 1) : (i += 1) {
+            v.*.appendAssumeCapacity(false);
+        }
+        v.*.appendAssumeCapacity(true);
+        if (it.next()) |l| {
+            line = l;
+        } else {
+            break;
+        }
+    }
+    const lastX = width - 1;
+    const lastY = heights.items.len - 1;
+    // init first and last lines edges
+    var x: usize = 1;
+    while (x < width - 1) : (x += 1) {
+        visibility.items[0].items[x] = true;
+        visibility.items[lastY].items[x] = true;
+    }
+    // calculate visible trees in lines
+    var y: usize = 1;
+    while (y < lastY) : (y += 1) {
+        const treeline = heights.items[y];
+        // look right
+        var max = treeline.items[0];
+        x = 1;
+        while (x < lastX) : (x += 1) {
+            if (treeline.items[x] > max) {
+                visibility.items[y].items[x] = true;
+                max = treeline.items[x];
+            }
+        }
+        // look left
+        max = treeline.items[lastX];
+        x = lastX - 1;
+        while (x > 0) : (x -= 1) {
+            if (treeline.items[x] > max) {
+                visibility.items[y].items[x] = true;
+                max = treeline.items[x];
+            }
+        }
+    }
+    // calculate visible trees in columns
+    x = 1;
+    while (x < lastX) : (x += 1) {
+        // look down
+        var max = heights.items[0].items[x];
+        y = 1;
+        while (y < lastY) : (y += 1) {
+            if (heights.items[y].items[x] > max) {
+                visibility.items[y].items[x] = true;
+                max = heights.items[y].items[x];
+            }
+        }
+        // look up
+        max = heights.items[lastY].items[x];
+        y = lastY - 1;
+        while (y > 0) : (y -= 1) {
+            if (heights.items[y].items[x] > max) {
+                visibility.items[y].items[x] = true;
+                max = heights.items[y].items[x];
+            }
+        }
+    }
+    // calculate total
+    var tot: usize = 0;
+    y = 0;
+    while (y <= lastY) : (y += 1) {
+        x = 0;
+        while (x <= lastX) : (x += 1) {
+            if (visibility.items[y].items[x]) {
+                tot += 1;
+            }
+        }
+    }
+    return tot;
+}
diff --git a/2022/08-treetop-tree-house/input b/2022/08-treetop-tree-house/input
new file mode 100644
index 0000000..ffdd5b1
--- /dev/null
+++ b/2022/08-treetop-tree-house/input
@@ -0,0 +1,99 @@
+011201001000123232122300403211332202122424332111151523152310403222120311202224013311113203311122001
+102201211220103202323002411123324024134251423232343141424431144431022143443131141222323122010012220
+002022232232102013311311301321044421352134513235443522243113311323213013301030440423203311103101020
+002212021110130112400112141310424411421435324412235335534245212325313312413434430114302030310200000
+202000312203303110042324124431114212153432535412115323131323541522511253002131401212012131031321110
+120203002030304244102444143021314124552253521343321513511124144454343454102412220143321013220111212
+012133330030200444414333325255125142322121412245551424242135123513411533153323130432231002121211210
+012300220003100211444401144353345522135453435223464636451554321531323513234331131114224102232333310
+000201310302031301344341134512444312432566266533252332656654251123535525135213300040211242011230031
+121002133124022203240512452433331223524622643252532325346635555552514352434233454024134201432001111
+112213110140442401434531255323512525265655352543623565556265545555235551143135124203142220020302000
+033001202421424143555311243322416262636322654432542644633525453666655354514351121150231101002002310
+133303044321221102531154151541224245536464535622566355532543644552554644312231415325142303020031312
+112333344411024045335422225146442243536464622553556234523445362524655623435243115242532313102020021
+123023422310204444121415255225254435644446326664473564435422565325224635623542352154120001224144312
+102303024142131515433355242322223363453633455657436436574636544336652564626641215232314243234004001
+021344140434455245134415553542352643537665534644574553367446664254532523624521243554252411433032112
+100140101131444142414254644644434663647646555637737475474473636562243265243536422253531252202124322
+111043301134142345422324342454235374733474673456744577746755765343355535622342432251442244140231224
+232120141224122324244532255543256467566454337465647735433663734756446566663442525425254525142212311
+102310340244433433553362546534535757453376643763344566566557634664535744445254533545223521213213014
+330111232252114431226334564636467643777466445537346735563633337744734474466254662225321443542401243
+344311321253412213666443354643647347656735478884748547564466577774737677363226422622515344334010341
+222340105234132533423442424376674757757675647476557547564445666676437755355626455436313331225343402
+334241221121414455435265324646757456774784864846746867457546648735456677555624445353555434433340341
+333430021343121666326363537633737767788775478777445558858444854755434544735362564626265444342330020
+332224425333452333556456745375454657668644877658744844547774765844454475434765533256545152435214410
+411322431421116436336347456774356844455867864644844878664785864444475567664473365652253123453220003
+130345455115155526426437663665665668576686587847778476557678655576775553535745643522532344433523042
+241333521455132466523664543556384776587787745658797755565556576546847447434775733626365325451531301
+202135433134452323646546565545646885747548679876767658578565476458486465755545465664435422532454541
+344025243154435524235475655536845545775797795959686975588855546544875685664377465455353661444452422
+120511445324333353265334766654858656857755669695597899959957757545465687447345336332322634434414522
+041425252513666643357433333888555778459755889566967799659865567757457567576463765323236366123221323
+142343534134652443554434768544658774587669979986775985989879787975445856456554364645323653454511323
+443155144123223566654765746758688875856899955996667659755976778586644774777456744653322566354532232
+013242522162435447764573774877757879868788876799896979576555597985885468586473474464455426633333452
+101431333345553353553337548577478656967866886877887889699999856979976485874455544477534422463331314
+422325541533664573334736464857446675995799977868697688998787757585668584775766563477536636621514142
+313315332565562573637376866486547776557979868979996867779966955885566785455767644565336236452541411
+231122455364326235655644685888786685587796897688777698977986787596655865857448333576665523356143332
+314415154446535337443754887576795586569678967879977696896667866768856785586774365336636426455324541
+251324556334435537567468544665859588888869687767876697967887867856679658788866355353346553442543353
+134353225423362456734666455757877769577678987866887877799886886885859796767664444665534363236114533
+251241346545626367667578575687955957988796678987999979977897978877579787844755554533763646262143315
+353543555544353753474346565789555799696999667888997899777669899867697878476845756644734243432245123
+221521465632632737777766744748678869769669668898887888987898666789869785645678734643552655525624335
+351552456455622567337644647486678857766866879798779999878779869885869788874885873744772665326352324
+153242153665224557353455465857685566797887699998988788877767696668668675666664465757646436665554315
+321113152666424547657348876876678597898779877779998999978978777885976658558676664444674243656333212
+421511245364456777655754476646885699898678788797778788778778999795687589454774563737333365434325525
+213532265252653474345766566877669898969767779777879797899977669868595997784466766655547455234435452
+125232235356525353764645486577668857868788699799787978898988669878688867586564457353673236664223343
+441242562562223643773466848558599657669669968987979987787969676777796877655876456745562442232541525
+135122156635652746574578664849659556998698797778797889988788869797687977855447474475546334662522444
+144315413442434666777478887855885568968799966889978797797867786966685589646488554737453225335213325
+511213234443636433646678657654587788667696879878989799867699988765895758788675765445656425425334544
+052145146243336363474565857687976889776768867898889967686967668565998666768575534675445244546424155
+235513424332444756467574556745997958679678999799789777998968876679956958746554677637762355253554335
+331155256654246447545776676487485655676699678967897779688898989999768655488874564764434223445132152
+152152253254255234473347878744485766678897879689897888667968795675655864748584644653323363464154251
+245154344235223346354765457746867586969968687876867899766986679689585778787473555663424264553541344
+235253541263666477544377746867785766579566868896689699876766695956667455774677646576554255521144355
+033522343456423455634354575764856898657669957896677776766596688857787474488436433455326554242331222
+321532413246333226435563556578864759978657759897896799958558598588975755858856537673332523244522141
+101422552442534324467345475684574877989759655788785857697957976679848768474665346435664653421242444
+103425135453353666736674677847548667967885667765576995797857589796866646565443377775564436443333543
+041131245522253556554636537878457787468577768876778599999689667978487755747676763666266652435545351
+424232344536333364556466767555646468677996965895798968676966868665587584664535544755645232211324114
+334034423343366322247357747635787857555667756956768657779596877655676555367754633345545442422145333
+424344345121532564223643563774744574746844686888885779565686455664565643634566756543362551431252401
+232123114442152332546734767375678475664877645798695799654765488755876545334345452455463633534433233
+414423121145222454332477456654436757485685646546884446667744645744675377357654436554353221451345404
+234130223314353235262655676637577858558554556467788664555466588778677546456334642623666524333250443
+414001252524152463224524734765775677644765886656877578666575855788653533364773455446565352432424320
+024323134311552535243564667476365737764685474446876486685546667685363735646643655435355533243440034
+331141044111451522226436327536773637654887585478885586588745847444466365767232265352211455413531431
+241321311312323233252665352455436545735388846445565487667644555744667753556266645332452431541341044
+234030032312154414563442653244476576544654676884777445766434443476675746365245632242515342521301442
+202112004552434344564624422526757574735736566643654737673776743354737744242533546523434111443034202
+323422334452422412134566522262537334374446646774476534347655656336555632626663364214333341322443300
+031243421344143515452456444553266345437737337675574563437533573575456463665443432215213541123241240
+002114441013421154331235436253442576764555535635775735635377573353666526333623554524421352131443020
+111342301013125124521245222663363363467436357434736773473777464564655622533254352444544553311114233
+222323000331131531351433363334345533653474663466435557365553376535246564324662454422135233103003200
+002103300342403311123432563445263435443255635353333564444573456633466424623313351545133022013122320
+300304042333200223123432352234525626625234236453763536563235242224645265643515312312520000242200000
+210121244033001141551213125554433445222532265463624234562324443435344362451243522525243002401410013
+303323342040431313415255233251226626334264553655346266323665655652522363324341123235410333230402230
+300112203021311400115231251543524354554262365526643622264625434236554412121342322522123434120120203
+011001023222004142422445443143212526654365444643442536365453622222634154551441553400220414300301332
+230032020342121242113341435444543253355352433246243543645634456552525315313143243431133302112320020
+232132202131312144424224413332214322543242664652323324456222615212244414145113442320023403200012111
+112222030320432400004224215552515412325221525356363643351335211141344255554442403013303120331312202
+110321230332323212301432002424211134155124241552254334221154111545254253122214132321141212032221001
+021020121321302320401011302153145251455114411155452245422422135453412153112033343412340101230302010
+122203012232330222213342133012334131225335225325343355122151154444535354414423434423220001330003020
+221120213213221333210131242440001425551432522221141211124544343151315104244333311124033221102312011
+202201033331203122413021242022211002455531321354252412214332215513311231404032244320020330332301120
diff --git a/2022/08-treetop-tree-house/second.zig b/2022/08-treetop-tree-house/second.zig
new file mode 100644
index 0000000..3582143
--- /dev/null
+++ b/2022/08-treetop-tree-house/second.zig
@@ -0,0 +1,101 @@
+const std = @import("std");
+
+const example = @embedFile("example");
+const input = @embedFile("input");
+
+pub fn main() anyerror!void {
+    var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
+    defer arena.deinit();
+    const allocator = arena.allocator();
+
+    try std.testing.expectEqual(try solve(example, allocator), 8);
+    const result = try solve(input, allocator);
+    try std.io.getStdOut().writer().print("{}\n", .{result});
+}
+
+fn solve(puzzle: []const u8, allocator: std.mem.Allocator) !u64 {
+    var it = std.mem.tokenize(u8, puzzle, "\n");
+    var heights = std.ArrayList(std.ArrayList(u8)).init(allocator);
+    var scenic = std.ArrayList(std.ArrayList(u64)).init(allocator);
+    // process input
+    var line = it.next() orelse unreachable;
+    const width = line.len;
+    while (true) {
+        var h = try heights.addOne();
+        var v = try scenic.addOne();
+        h.* = try std.ArrayList(u8).initCapacity(allocator, width);
+        v.* = try std.ArrayList(u64).initCapacity(allocator, width);
+        try h.*.writer().writeAll(line);
+        var i: usize = 0;
+        while (i < width) : (i += 1) {
+            v.*.appendAssumeCapacity(0);
+        }
+        if (it.next()) |l| {
+            line = l;
+        } else {
+            break;
+        }
+    }
+    const lastX = width - 1;
+    const lastY = heights.items.len - 1;
+    // init first and last lines edges
+    var x: usize = 1;
+    while (x < width - 1) : (x += 1) {
+        scenic.items[0].items[x] = 0;
+        scenic.items[lastY].items[x] = 0;
+    }
+    // calculate scenic scores tree by tree
+    var tot: usize = 0;
+    var y: usize = 1;
+    while (y < lastY) : (y += 1) {
+        x = 1;
+        while (x < lastX) : (x += 1) {
+            const max = heights.items[y].items[x];
+            // look right
+            var sr: usize = 1; // scenic score to the right
+            var i: usize = x + 1;
+            while (i < lastX) : (i += 1) {
+                if (heights.items[y].items[i] < max) {
+                    sr += 1;
+                } else {
+                    break;
+                }
+            }
+            // look left
+            var sl: usize = 1;
+            i = x - 1;
+            while (i > 0) : (i -= 1) {
+                if (heights.items[y].items[i] < max) {
+                    sl += 1;
+                } else {
+                    break;
+                }
+            }
+            // look down
+            var sd: usize = 1;
+            i = y + 1;
+            while (i < lastY) : (i += 1) {
+                if (heights.items[i].items[x] < max) {
+                    sd += 1;
+                } else {
+                    break;
+                }
+            }
+            // look up
+            var su: usize = 1;
+            i = y - 1;
+            while (i > 0) : (i -= 1) {
+                if (heights.items[i].items[x] < max) {
+                    su += 1;
+                } else {
+                    break;
+                }
+            }
+            const score = sr * sl * sd * su;
+            if (score > tot) {
+                tot = score;
+            }
+        }
+    }
+    return tot;
+}
-- 
cgit v1.2.3