Terribly inefficient. But hey, it works!

master
Dustin Swan 5 months ago
parent 080ff61267
commit 5ba7e6e4e1
Signed by: dustinswan
GPG Key ID: AB49BD6B2B3A6377

@ -0,0 +1,247 @@
seeds: 487758422 524336848 2531594804 27107767 1343486056 124327551 1117929819 93097070 3305050822 442320425 2324984130 87604424 4216329536 45038934 1482842780 224610898 115202033 371332058 2845474954 192579859
seed-to-soil map:
152560994 173671324 63296280
22185606 1527272669 123700133
1331635416 297391996 25501160
2532562923 236967604 60424392
145885739 854580877 6675255
696074404 427174664 330582271
0 1407203152 22185606
1174684019 152310608 21360716
2679050525 3516671293 482421092
1227353908 322893156 104281508
1077860077 757756935 96823942
3161471617 3999092385 22763615
1509447184 1650972802 82059456
4170512486 2802241718 1263617
1196044735 1495963496 31309173
1357136576 0 152310608
4171776103 2679050525 123191193
1731875772 1733032258 319590386
282432012 1001625264 405577888
215857274 1429388758 66574738
1026656675 2541783913 51203402
1591506640 861256132 140369132
688009900 2052622644 8064504
3457346528 2803505335 713165958
3184235232 4021856000 273111296
2051466158 2060687148 481096765
soil-to-fertilizer map:
2587123207 1612631011 14556918
425896400 1627187929 180219453
974395525 3228073255 181091940
606115853 2482605187 15274968
621390821 1843957593 329096619
4269010275 3749182981 25957021
2601680125 1807407382 36550211
3749182981 3775140002 91697225
3337986166 2411426158 71179029
2306503017 631361705 276943999
0 205465305 425896400
950487440 181557220 23908085
1155487465 1188132368 424498643
1579986108 2497880155 726516909
2583447016 3224397064 3676191
3840880206 3866837227 428130069
3099614220 2173054212 238371946
2918057000 0 181557220
2638230336 908305704 279826664
fertilizer-to-water map:
0 226390191 111676682
342717440 10141562 176981703
3507713259 629378619 187481170
3695194429 3739990160 60489319
2747106431 4155961766 11528550
2120906094 2661985654 77106422
3983043532 1233406588 239832885
3045388563 4287081612 7885684
529840705 187123265 39266926
2198012516 1102191084 16615097
3053274247 4167490316 104130064
2564366436 2756374717 129809025
3331241613 816859789 87383675
3418625288 3536806097 36187146
1239632010 3393454292 143351805
1147966039 1776147938 91665971
1382983815 2230578660 82475007
4222876417 1045170068 57021016
3455914127 2313053667 4640764
2835800762 3800479479 42590884
4279897433 1473239473 15069863
3780709534 2342720217 202333998
1753297424 3902953503 253008263
1465458822 1488309336 287838602
3454812434 2588893134 1101693
3287402694 2545054215 43838919
2704024450 1002088087 43081981
629378619 2589994827 71990827
3189558071 904243464 97844623
2214627613 2886183742 264407413
2006305687 1118806181 114600407
3460554891 1867813909 47158368
3755683748 2317694431 25025786
111676682 338066873 231040758
519699143 0 10141562
2479035026 3313735125 69870178
2548905204 4271620380 15461232
2775917622 3843070363 59883140
3157404311 2198424900 32153760
864513416 1914972277 283452623
2758634981 2739092076 17282641
701369446 3150591155 163143970
2878391646 3572993243 166996917
2694175461 3383605303 9848989
water-to-light map:
1222332482 2306154207 322881400
3721269109 3329751112 30895612
4157109606 3191893422 137857690
2602036554 3676681423 255279159
2293973174 3078247260 113646162
1208052724 2246358310 14279758
1835200232 1597610395 302070784
3118371905 1208052724 389557671
2137271016 3519979265 156702158
2501933666 1952285487 54586749
3753874345 1899681179 52604308
3806478653 3931960582 7636192
3973340148 2006872236 24436917
3814114845 2629035607 159225303
3507929576 2031309153 213339533
3752164721 2244648686 1709624
2857315713 3939596774 261056192
3997777065 3360646724 159332541
2556520415 2260638068 45516139
2407619336 4200652966 94314330
1545213882 2788260910 289986350
light-to-temperature map:
40645637 589707204 89929230
2331703372 3634092968 247989827
375013050 880330876 388603146
959059361 861524497 18806379
3081535248 2703807387 671456921
2080450790 1678532701 100545991
1520717011 1522300302 156232399
3801827392 4285326304 9640992
2834731556 1990942492 115059472
2949791028 2566169187 71005535
3020796563 4224587619 60738685
4159346802 1855321998 135620494
977865740 0 297257755
3811468384 3375264308 157802817
2304295289 1779078692 27408083
3752992169 1806486775 48835223
2579693199 3882082795 255038357
130574867 328095764 236983298
4081903724 3533067125 77443078
367558165 310812857 7454885
3969271201 3610510203 23582765
4080320433 1520717011 1583291
777171298 679636434 181888063
2180996781 2106001964 56665843
3992853966 4137121152 87466467
0 1268934022 6189473
30817615 318267742 9828022
1676949410 2162667807 403501380
763616196 297257755 13555102
6189473 565079062 24628142
2237662624 2637174722 66632665
temperature-to-humidity map:
3854764317 3086190444 332386294
2110554705 1096342109 65650849
3236082645 1211923153 20175736
846106827 1853452836 60731419
596073066 1972015961 100470927
1202254149 2647779239 280062599
2176205554 2107199879 422980149
2943801812 432921932 58618218
1824616452 1161992958 3317671
1201112206 2106057936 1141943
1840640266 1631373972 178403432
2767591984 62542954 155027747
2743880612 491540150 8409669
62542954 1273100182 24571446
4208015516 3772661112 86951780
3477752908 217570701 215351231
2019043698 3681150105 91511007
1482316748 4027597725 172205397
766244356 4199803122 79862471
950513678 665972626 23438579
89279871 1232098889 41001293
1654522145 1914184255 36130017
3002420030 3660808941 20341164
452765307 1525178112 98766078
551531385 840194947 44541681
1827934123 2072486888 12706143
87114400 3859612892 2165471
1091551468 3873351076 109560738
2714852730 884736628 29027882
906838246 1809777404 43675432
760232399 1297671628 6011957
696543993 3861778363 11572713
3693104139 633914109 32058517
1690652162 499949819 133964290
151982853 3418576738 142433848
2922619731 689411205 21182081
2599185703 1165310629 46612524
2752290281 4279665593 15301703
3022761194 913764510 182577599
2645798227 3561010586 69054503
130281164 1950314272 21701689
973952257 2530180028 117599211
715546488 3982911814 44685911
4187150611 2085193031 20864905
3256258381 1303683585 221494527
3725162656 710593286 129601661
708116706 1623944190 7429782
3205338793 3630065089 30743852
294416701 2927841838 158348606
humidity-to-location map:
3745579304 2724582328 81388084
2201043082 981698567 150857305
456470998 689872919 41258774
2351900387 2312761976 47825019
497729772 314502888 115122928
4036836228 4279991461 14975835
784121118 3255986437 5687937
612852700 0 118278993
3894168411 842107405 27168107
3127730376 4061803810 218187651
1230572305 1958697503 125808488
304425981 163566931 106757079
789809055 3790646012 241507252
1777374448 1871672054 39148062
1816522510 1504159194 367512860
235721965 621168903 68704016
4051812063 1480547431 14406303
3826967388 1228960483 58471320
411183060 118278993 45287938
3921336518 869275512 103693352
4025029870 2304659906 8102070
2838210137 1132555872 96404611
2934614748 1287431803 193115628
1414367080 3422182046 363007368
3345918027 1494953734 9205460
2184035370 2805970412 17007712
2631131158 2088210279 207078979
1356380793 784121118 57986287
2399725406 2493176576 231405752
1031316307 3261674374 160507672
44178878 429625816 191543087
4195166765 3165556554 90429883
4285596648 2295289258 9370648
3403000874 2822978124 342578430
1191823979 3785189414 5456598
1197280577 2459884848 33291728
4066218366 4032153264 29650546
3355123487 1910820116 47877387
3885438708 972968864 8729703
0 270324010 44178878
4095868912 2360586995 99297853
4033131940 2084505991 3704288

@ -0,0 +1,141 @@
const std = @import("std");
const Range = struct { destination: u64, source: u64, length: u64 };
const Map = struct { from: []const u8, to: []const u8, ranges: std.ArrayList(Range) };
pub fn main() !void {
const content = @embedFile("data.txt");
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const allocator = gpa.allocator();
// split the file content on empty lines
var sections = std.mem.split(u8, content, "\n\n");
// parse out the first line, collecting seeds into an ArrayList
var seedSection = std.mem.split(u8, sections.next().?, " ");
var seeds = std.ArrayList(u64).init(allocator);
defer seeds.deinit();
_ = seedSection.next();
while (seedSection.next()) |s| {
try seeds.append(try std.fmt.parseInt(u64, s, 10));
}
var maps = std.ArrayList(Map).init(allocator);
defer maps.deinit();
// iterate over each section, parse into Map structs, append them onto the maps ArrayList
while (sections.next()) |s| {
var lines = std.mem.split(u8, s, "\n");
var firstLine = lines.next().?;
var words = std.mem.split(u8, firstLine, " ");
// grab the first "word" of the first line, and split it on -
var parts = std.mem.split(u8, words.next().?, "-");
const from = parts.next().?;
_ = parts.next();
const to = parts.next().?;
var ranges = std.ArrayList(Range).init(allocator);
// TODO: do I need to deinit ranges... somewhere?
while (lines.next()) |line| {
if (line.len == 0) {
continue;
}
var nums = std.mem.split(u8, line, " ");
var destination = try std.fmt.parseInt(u64, nums.next().?, 10);
var source = try std.fmt.parseInt(u64, nums.next().?, 10);
var length = try std.fmt.parseInt(u64, nums.next().?, 10);
const range = Range{ .destination = destination, .source = source, .length = length };
try ranges.append(range);
}
const map = Map{ .from = from, .to = to, .ranges = ranges };
try maps.append(map);
}
var lowestLocation: ?u64 = null;
for (seeds.items) |seed| {
// loop starting from the "seed" map until we have a location
var from: []const u8 = "seed";
var val = seed;
while (!std.mem.eql(u8, from, "location")) {
const map = findMap(from, maps).?;
val = findNewValue(val, map);
from = map.to;
}
if (lowestLocation) |l| {
if (val < l) {
lowestLocation = val;
}
} else {
lowestLocation = val;
}
}
std.debug.print("Part 1 {?d}\n", .{lowestLocation});
// Part 2
// Can we go backwards?
var i: u64 = 0;
outer: while (true) {
var to: []const u8 = "location";
var val = i;
while (!std.mem.eql(u8, to, "seed")) {
const map = findMapReverse(to, maps).?;
val = findNewValueReverse(val, map);
to = map.from;
}
var idx: u8 = 0;
while (idx < seeds.items.len) : (idx += 2) {
const lower = seeds.items[idx];
const upper = lower + seeds.items[idx + 1];
if (val >= lower and val < upper) {
break :outer;
}
}
i += 1;
}
std.debug.print("Part 2 {?d}\n", .{i});
}
// given the "from" type, find the map that we should follow
fn findMap(from: []const u8, maps: std.ArrayList(Map)) ?Map {
for (maps.items) |map| {
if (std.mem.eql(u8, map.from, from)) {
return map;
}
}
return null;
}
fn findNewValue(val: u64, map: Map) u64 {
for (map.ranges.items) |r| {
if (val >= r.source and val < r.source + r.length) {
return r.destination + val - r.source;
}
}
// if no range fits, return the original value
return val;
}
// given the "to" type, find the map that we should follow
fn findMapReverse(to: []const u8, maps: std.ArrayList(Map)) ?Map {
for (maps.items) |map| {
if (std.mem.eql(u8, map.to, to)) {
return map;
}
}
return null;
}
fn findNewValueReverse(val: u64, map: Map) u64 {
for (map.ranges.items) |r| {
if (val >= r.destination and val < r.destination + r.length) {
return r.source + val - r.destination;
}
}
// if no range fits, return the original value
return val;
}

@ -0,0 +1,33 @@
seeds: 79 14 55 13
seed-to-soil map:
50 98 2
52 50 48
soil-to-fertilizer map:
0 15 37
37 52 2
39 0 15
fertilizer-to-water map:
49 53 8
0 11 42
42 0 7
57 7 4
water-to-light map:
88 18 7
18 25 70
light-to-temperature map:
45 77 23
81 45 19
68 64 13
temperature-to-humidity map:
0 69 1
1 0 69
humidity-to-location map:
60 56 37
56 93 4
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