From b26a3830d2c0fd0d27b411adc57757cf20b80d37 Mon Sep 17 00:00:00 2001
From: Lars Martens <lars@martens.red>
Date: Sun, 5 Dec 2021 11:38:31 +0100
Subject: [PATCH] Day 5

---
 input/05-test.txt |  10 +
 input/05.txt      | 500 ++++++++++++++++++++++++++++++++++++++++++++++
 src/bin/05.rs     | 116 +++++++++++
 3 files changed, 626 insertions(+)
 create mode 100644 input/05-test.txt
 create mode 100644 input/05.txt
 create mode 100644 src/bin/05.rs

diff --git a/input/05-test.txt b/input/05-test.txt
new file mode 100644
index 0000000..b258f68
--- /dev/null
+++ b/input/05-test.txt
@@ -0,0 +1,10 @@
+0,9 -> 5,9
+8,0 -> 0,8
+9,4 -> 3,4
+2,2 -> 2,1
+7,0 -> 7,4
+6,4 -> 2,0
+0,9 -> 2,9
+3,4 -> 1,4
+0,0 -> 8,8
+5,5 -> 8,2
diff --git a/input/05.txt b/input/05.txt
new file mode 100644
index 0000000..fd2a6c3
--- /dev/null
+++ b/input/05.txt
@@ -0,0 +1,500 @@
+242,601 -> 242,18
+938,357 -> 938,128
+920,574 -> 750,574
+804,978 -> 804,813
+955,932 -> 68,45
+232,604 -> 232,843
+69,570 -> 467,968
+355,432 -> 611,688
+945,19 -> 700,19
+904,932 -> 904,918
+455,65 -> 516,65
+571,485 -> 588,485
+717,142 -> 217,142
+377,344 -> 66,344
+510,818 -> 132,818
+848,709 -> 848,950
+785,50 -> 785,857
+23,981 -> 971,33
+938,45 -> 938,327
+212,402 -> 601,13
+749,142 -> 651,240
+94,930 -> 22,930
+436,467 -> 820,851
+544,265 -> 458,265
+517,708 -> 517,785
+957,893 -> 957,22
+684,610 -> 526,452
+713,687 -> 526,687
+220,781 -> 988,13
+12,45 -> 912,945
+854,677 -> 646,677
+382,498 -> 382,64
+676,879 -> 148,351
+809,52 -> 336,525
+959,951 -> 41,33
+943,162 -> 132,973
+897,732 -> 897,308
+21,196 -> 702,877
+938,972 -> 656,972
+798,139 -> 90,847
+213,597 -> 582,966
+248,955 -> 973,230
+985,606 -> 985,885
+166,693 -> 804,693
+807,897 -> 28,118
+433,306 -> 433,447
+899,61 -> 60,900
+984,582 -> 691,582
+803,583 -> 910,583
+348,142 -> 348,244
+352,775 -> 352,430
+240,285 -> 240,406
+394,541 -> 394,655
+887,622 -> 298,33
+62,37 -> 861,836
+819,136 -> 29,926
+717,332 -> 717,408
+709,63 -> 276,496
+384,441 -> 150,441
+292,251 -> 557,516
+518,311 -> 52,777
+50,735 -> 479,306
+932,865 -> 139,72
+43,21 -> 982,960
+63,927 -> 796,194
+958,351 -> 958,623
+643,451 -> 35,451
+534,14 -> 459,14
+20,649 -> 924,649
+983,18 -> 35,966
+84,668 -> 203,668
+40,654 -> 748,654
+474,760 -> 85,371
+512,431 -> 272,431
+588,93 -> 112,569
+648,687 -> 832,687
+988,867 -> 116,867
+979,46 -> 94,931
+242,307 -> 800,865
+100,204 -> 807,911
+890,962 -> 88,962
+273,510 -> 273,201
+184,748 -> 813,119
+214,915 -> 950,179
+960,975 -> 89,104
+853,347 -> 853,79
+853,308 -> 884,308
+245,394 -> 245,640
+850,554 -> 604,800
+141,159 -> 141,378
+635,632 -> 897,894
+352,182 -> 550,182
+748,613 -> 748,887
+531,664 -> 255,388
+785,414 -> 432,767
+374,457 -> 653,736
+451,535 -> 444,535
+600,179 -> 434,13
+489,605 -> 845,961
+658,786 -> 658,196
+305,556 -> 305,914
+820,368 -> 204,984
+903,70 -> 548,425
+840,450 -> 796,494
+289,183 -> 768,662
+21,54 -> 950,983
+765,294 -> 209,850
+467,511 -> 703,747
+354,645 -> 730,645
+176,30 -> 964,818
+290,259 -> 345,259
+868,945 -> 96,173
+536,884 -> 536,94
+415,177 -> 415,99
+250,140 -> 466,140
+900,107 -> 900,249
+74,394 -> 137,394
+364,957 -> 364,81
+718,477 -> 718,227
+27,14 -> 988,975
+491,956 -> 154,956
+289,283 -> 289,225
+479,583 -> 604,583
+581,406 -> 23,964
+837,526 -> 732,526
+417,435 -> 417,206
+502,184 -> 20,666
+903,754 -> 817,668
+381,284 -> 967,870
+31,17 -> 176,17
+225,377 -> 179,377
+316,932 -> 358,890
+605,841 -> 559,841
+865,193 -> 865,827
+836,834 -> 142,140
+229,610 -> 232,610
+26,13 -> 872,859
+26,444 -> 26,79
+272,690 -> 531,949
+964,954 -> 331,954
+545,91 -> 335,91
+906,942 -> 906,301
+608,778 -> 608,364
+475,723 -> 475,710
+454,207 -> 614,207
+200,180 -> 917,897
+966,44 -> 71,939
+288,252 -> 288,413
+795,791 -> 66,62
+81,39 -> 588,546
+249,244 -> 892,244
+483,579 -> 853,579
+220,921 -> 220,286
+917,834 -> 675,834
+569,692 -> 569,521
+344,586 -> 835,95
+116,153 -> 888,925
+681,52 -> 871,242
+980,976 -> 27,23
+828,567 -> 482,567
+660,432 -> 660,441
+826,379 -> 280,379
+42,839 -> 259,622
+743,23 -> 91,23
+318,400 -> 318,528
+539,745 -> 734,940
+831,194 -> 831,210
+582,630 -> 361,851
+284,900 -> 213,829
+52,855 -> 763,855
+215,753 -> 452,753
+290,187 -> 417,187
+69,48 -> 69,126
+76,628 -> 76,365
+257,694 -> 54,694
+755,713 -> 556,912
+519,265 -> 342,265
+193,319 -> 193,651
+496,231 -> 900,231
+83,942 -> 83,524
+524,59 -> 989,524
+288,800 -> 907,181
+458,138 -> 586,138
+338,244 -> 934,840
+843,728 -> 843,476
+42,634 -> 657,19
+827,634 -> 369,176
+779,900 -> 779,503
+20,20 -> 870,870
+467,241 -> 467,142
+677,483 -> 501,483
+10,989 -> 989,10
+11,989 -> 989,11
+244,750 -> 244,607
+479,497 -> 48,928
+372,341 -> 615,341
+817,941 -> 339,941
+352,67 -> 352,581
+590,747 -> 590,405
+524,26 -> 524,37
+501,300 -> 117,300
+265,194 -> 491,420
+397,891 -> 983,305
+423,717 -> 423,922
+197,863 -> 197,217
+12,91 -> 379,91
+364,426 -> 364,185
+649,835 -> 649,309
+517,380 -> 485,380
+328,469 -> 568,469
+781,298 -> 781,264
+25,794 -> 25,197
+570,744 -> 570,544
+664,352 -> 632,320
+528,944 -> 528,696
+242,44 -> 900,702
+486,775 -> 486,556
+608,245 -> 788,245
+114,11 -> 114,508
+751,560 -> 751,884
+211,513 -> 448,513
+389,219 -> 308,300
+638,200 -> 105,200
+258,243 -> 365,243
+120,558 -> 556,122
+787,166 -> 274,166
+617,666 -> 185,234
+537,172 -> 808,172
+633,980 -> 282,980
+270,150 -> 270,225
+925,32 -> 48,909
+979,14 -> 891,102
+98,278 -> 98,485
+333,771 -> 119,771
+132,673 -> 132,189
+416,470 -> 482,404
+762,151 -> 925,151
+148,721 -> 378,491
+255,576 -> 255,474
+21,48 -> 938,965
+876,615 -> 777,615
+713,209 -> 209,209
+250,474 -> 271,453
+684,71 -> 451,71
+406,614 -> 519,501
+479,252 -> 112,252
+721,768 -> 284,331
+290,344 -> 290,111
+359,934 -> 544,934
+754,976 -> 726,976
+358,544 -> 358,904
+597,344 -> 597,581
+915,222 -> 915,255
+931,160 -> 135,956
+160,657 -> 348,657
+35,942 -> 949,28
+298,837 -> 298,356
+540,195 -> 540,119
+29,140 -> 29,955
+118,117 -> 980,979
+240,384 -> 464,608
+677,667 -> 361,351
+982,987 -> 11,16
+638,770 -> 95,227
+135,285 -> 135,349
+843,313 -> 843,529
+208,220 -> 945,957
+450,889 -> 977,362
+876,69 -> 283,69
+57,586 -> 57,231
+602,78 -> 602,564
+708,704 -> 267,704
+697,336 -> 697,264
+564,522 -> 519,567
+195,217 -> 274,138
+35,885 -> 116,804
+680,28 -> 148,28
+736,34 -> 736,616
+918,454 -> 52,454
+143,40 -> 415,40
+985,469 -> 985,282
+804,703 -> 107,703
+707,59 -> 296,470
+37,935 -> 931,41
+45,723 -> 45,531
+897,959 -> 165,227
+691,948 -> 523,948
+545,560 -> 545,45
+251,24 -> 748,521
+625,506 -> 625,626
+302,702 -> 989,15
+489,926 -> 489,507
+405,830 -> 405,871
+736,851 -> 19,134
+712,848 -> 48,184
+925,914 -> 33,22
+593,254 -> 369,478
+965,691 -> 155,691
+758,931 -> 349,522
+64,135 -> 820,891
+79,933 -> 79,683
+609,454 -> 233,454
+617,853 -> 309,545
+695,130 -> 695,578
+508,198 -> 363,198
+184,414 -> 275,505
+627,901 -> 519,901
+765,715 -> 213,715
+445,134 -> 669,134
+785,33 -> 302,516
+563,218 -> 470,125
+136,461 -> 264,461
+523,643 -> 674,643
+473,695 -> 473,235
+616,835 -> 757,976
+406,763 -> 406,224
+483,111 -> 203,111
+70,863 -> 922,11
+738,141 -> 738,54
+146,697 -> 332,883
+939,16 -> 23,932
+836,15 -> 317,534
+853,586 -> 853,596
+733,377 -> 733,461
+378,597 -> 378,640
+522,225 -> 522,78
+875,886 -> 875,130
+302,83 -> 771,83
+969,588 -> 419,38
+268,159 -> 585,476
+658,955 -> 33,330
+940,149 -> 492,149
+157,254 -> 962,254
+265,778 -> 265,365
+414,494 -> 608,494
+27,959 -> 948,38
+220,160 -> 220,891
+836,316 -> 836,179
+843,727 -> 163,47
+225,695 -> 598,695
+678,249 -> 892,249
+938,36 -> 938,170
+190,486 -> 40,336
+815,256 -> 815,866
+961,200 -> 961,89
+67,895 -> 67,853
+480,727 -> 852,727
+334,94 -> 334,452
+67,622 -> 987,622
+48,29 -> 982,963
+90,29 -> 963,902
+859,739 -> 338,739
+869,254 -> 474,649
+196,43 -> 69,43
+336,439 -> 336,837
+248,387 -> 587,48
+378,729 -> 162,513
+699,658 -> 513,844
+447,410 -> 670,410
+739,593 -> 889,443
+83,970 -> 964,89
+276,406 -> 276,191
+860,75 -> 247,688
+435,858 -> 435,905
+691,893 -> 691,757
+136,896 -> 611,421
+693,211 -> 477,427
+181,793 -> 181,717
+674,326 -> 664,336
+938,826 -> 164,52
+833,380 -> 833,753
+833,349 -> 230,952
+662,870 -> 662,23
+974,511 -> 145,511
+38,579 -> 57,579
+966,965 -> 966,498
+641,217 -> 240,618
+418,986 -> 834,986
+971,716 -> 971,263
+254,313 -> 254,823
+61,790 -> 61,834
+262,439 -> 262,864
+345,856 -> 894,307
+736,862 -> 281,862
+814,636 -> 814,240
+853,865 -> 853,22
+792,106 -> 207,106
+647,303 -> 531,303
+506,706 -> 337,706
+402,140 -> 402,958
+899,796 -> 669,796
+806,619 -> 463,276
+340,347 -> 340,363
+18,21 -> 979,982
+395,214 -> 395,862
+228,330 -> 333,330
+723,950 -> 723,150
+392,298 -> 36,298
+916,118 -> 114,920
+210,854 -> 80,724
+212,206 -> 513,507
+44,659 -> 161,659
+771,44 -> 198,617
+485,706 -> 169,706
+385,455 -> 308,455
+390,317 -> 390,385
+492,532 -> 56,968
+237,674 -> 712,674
+988,909 -> 254,175
+86,276 -> 448,276
+688,418 -> 927,179
+667,773 -> 504,610
+968,974 -> 109,115
+843,54 -> 843,265
+19,249 -> 19,437
+307,326 -> 341,360
+531,891 -> 531,202
+281,535 -> 270,546
+503,305 -> 164,644
+170,971 -> 30,971
+763,247 -> 946,247
+795,920 -> 623,920
+673,16 -> 899,16
+785,845 -> 290,845
+68,614 -> 68,711
+284,984 -> 67,984
+787,942 -> 120,942
+953,369 -> 773,549
+927,727 -> 315,115
+884,686 -> 254,56
+432,276 -> 432,287
+658,99 -> 81,676
+622,917 -> 679,917
+938,978 -> 938,793
+945,15 -> 369,15
+603,709 -> 603,74
+670,422 -> 222,870
+190,702 -> 190,362
+354,349 -> 369,334
+26,880 -> 876,30
+636,31 -> 636,731
+778,628 -> 778,25
+23,483 -> 170,483
+23,972 -> 963,32
+725,308 -> 384,308
+97,962 -> 620,962
+136,929 -> 136,768
+656,295 -> 851,295
+125,801 -> 755,171
+120,32 -> 553,32
+698,196 -> 286,608
+66,721 -> 66,836
+931,680 -> 931,499
+862,449 -> 862,743
+71,143 -> 180,252
+510,327 -> 612,225
+932,874 -> 352,874
+599,372 -> 583,372
+821,770 -> 126,75
+317,186 -> 495,186
+557,710 -> 56,209
+895,866 -> 306,277
+571,948 -> 571,738
+287,864 -> 243,864
+802,728 -> 802,198
+711,642 -> 983,642
+969,922 -> 969,645
+89,417 -> 57,385
+567,967 -> 567,781
+350,498 -> 142,498
+92,931 -> 988,35
+980,940 -> 152,112
+55,944 -> 679,320
+669,410 -> 669,679
+151,431 -> 241,431
+984,882 -> 80,882
+431,374 -> 431,39
+30,91 -> 765,826
+730,228 -> 80,878
+379,570 -> 705,570
+67,398 -> 67,136
+491,515 -> 491,344
+396,453 -> 749,453
+203,660 -> 203,579
+912,900 -> 912,280
+909,88 -> 367,88
+41,942 -> 825,158
+724,417 -> 17,417
+463,536 -> 170,536
+715,737 -> 715,134
+627,453 -> 805,453
+934,795 -> 695,556
+404,729 -> 738,729
+973,685 -> 973,310
+563,348 -> 771,556
+716,232 -> 983,232
+975,183 -> 975,759
+934,958 -> 117,958
+538,806 -> 538,84
+695,677 -> 629,677
diff --git a/src/bin/05.rs b/src/bin/05.rs
new file mode 100644
index 0000000..f306151
--- /dev/null
+++ b/src/bin/05.rs
@@ -0,0 +1,116 @@
+use std::{cmp::Ordering, fmt::Display, iter};
+
+fn main() {
+    let mut f = Field::new(1000);
+    for line in input().filter(|line| line.col1 == line.col2 || line.row1 == line.row2) {
+        f.apply(line);
+    }
+    println!("First solution: {}", f.overlaps());
+
+    let mut f = Field::new(1000);
+    for line in input() {
+        f.apply(line);
+    }
+    println!("Second solution: {}", f.overlaps());
+}
+
+struct Field {
+    /// row-major encoding of the field
+    count: Vec<Vec<u32>>,
+}
+
+impl Field {
+    fn new(size: usize) -> Self {
+        Self {
+            count: vec![vec![0; size]; size],
+        }
+    }
+
+    fn apply(&mut self, line: Line) {
+        for (row, col) in line.points() {
+            self.count[row][col] += 1;
+        }
+    }
+
+    fn overlaps(&self) -> usize {
+        self.count
+            .iter()
+            .flat_map(|row| row.iter())
+            .filter(|&&n| n >= 2)
+            .count()
+    }
+}
+
+impl Display for Field {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        for row in 0..self.count.len() {
+            for col in 0..self.count.len() {
+                let c = match self.count[row][col] {
+                    0 => ".".to_string(),
+                    n if n <= 9 => n.to_string(),
+                    _ => "#".to_string(),
+                };
+                write!(f, "{}", c)?;
+            }
+            writeln!(f)?;
+        }
+        Ok(())
+    }
+}
+
+#[derive(Debug)]
+struct Line {
+    col1: usize,
+    row1: usize,
+    col2: usize,
+    row2: usize,
+}
+
+impl Line {
+    fn points(&self) -> impl Iterator<Item = (usize, usize)> {
+        self.row().zip(self.col()).take(self.len())
+    }
+    fn col(&self) -> Box<dyn Iterator<Item = usize>> {
+        match self.col1.cmp(&self.col2) {
+            Ordering::Less => Box::new(self.col1..=self.col2),
+            Ordering::Equal => Box::new(iter::repeat(self.col1)),
+            Ordering::Greater => Box::new((self.col2..=self.col1).rev()),
+        }
+    }
+    fn row(&self) -> Box<dyn Iterator<Item = usize>> {
+        match self.row1.cmp(&self.row2) {
+            Ordering::Less => Box::new(self.row1..=self.row2),
+            Ordering::Equal => Box::new(iter::repeat(self.row1)),
+            Ordering::Greater => Box::new((self.row2..=self.row1).rev()),
+        }
+    }
+    fn len(&self) -> usize {
+        let row = if self.row1 < self.row2 {
+            self.row2 - self.row1
+        } else {
+            self.row1 - self.row2
+        };
+        let col = if self.col1 < self.col2 {
+            self.col2 - self.col1
+        } else {
+            self.col1 - self.col2
+        };
+        col.max(row) + 1
+    }
+}
+
+fn input() -> impl Iterator<Item = Line> {
+    include_str!("../../input/05.txt")
+        .lines()
+        .map(|l| l.split_once(" -> ").unwrap())
+        .map(|(start, end)| {
+            let (x1, y1) = start.split_once(",").unwrap();
+            let (x2, y2) = end.split_once(",").unwrap();
+            Line {
+                col1: x1.parse().unwrap(),
+                row1: y1.parse().unwrap(),
+                col2: x2.parse().unwrap(),
+                row2: y2.parse().unwrap(),
+            }
+        })
+}