Day 19: Add C solution

2 files changed, 1078 insertions, 0 deletions

diff --git a/19/input.txt b/19/input.txt
new file mode 100644
index 0000000..4e5af1e
--- /dev/null
+++ b/19/input.txt
@@ -0,0 +1,949 @@
+--- scanner 0 ---
+-731,-763,-425
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+
+--- scanner 1 ---
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+
+--- scanner 2 ---
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+
+--- scanner 3 ---
+-561,681,-898
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+
+--- scanner 4 ---
+-720,-688,-429
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+
+--- scanner 5 ---
+699,-825,730
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+
+--- scanner 6 ---
+-716,-702,538
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+
+--- scanner 7 ---
+-582,-761,459
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+
+--- scanner 8 ---
+53,162,-22
+967,695,948
+770,-615,-548
+-670,-668,425
+968,599,931
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+-402,599,-642
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+
+--- scanner 9 ---
+523,-356,773
+-764,463,-560
+-425,-730,874
+668,-366,749
+728,-640,-825
+67,173,60
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+-787,551,-542
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+-682,846,572
+658,516,448
+518,532,446
+460,523,469
+94,-8,-68
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+691,-430,723
+
+--- scanner 10 ---
+632,619,803
+-337,-640,-546
+746,-937,-943
+-81,54,-168
+821,-857,548
+706,756,751
+683,-855,672
+-733,363,-817
+-615,381,-906
+-584,435,-808
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+-589,-913,412
+721,-864,422
+-601,-806,278
+397,451,-676
+-10,-104,0
+-604,404,408
+487,463,-794
+775,-762,-933
+-602,583,413
+-461,-925,315
+
+--- scanner 11 ---
+-746,899,-576
+407,869,433
+-547,-309,328
+-416,-384,339
+-316,-483,-310
+399,485,-678
+698,-432,802
+-46,-77,89
+-648,857,-455
+-726,877,401
+-478,-429,-312
+-744,850,-511
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+-729,896,666
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+-451,-326,327
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+359,887,502
+470,509,-563
+-434,-515,-324
+456,-804,-297
+-788,819,534
+779,-460,686
+597,-425,686
+
+--- scanner 12 ---
+363,-267,559
+256,-401,547
+-772,-682,-877
+314,-661,-725
+19,64,-38
+-676,-711,473
+-685,590,-796
+-833,-770,417
+-719,-516,-940
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+-625,644,776
+244,-304,419
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+-613,761,711
+-722,549,-776
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+-643,639,-799
+312,-537,-863
+305,-411,-763
+482,646,296
+-626,751,607
+
+--- scanner 13 ---
+292,-495,571
+651,919,779
+-175,-32,46
+-939,696,356
+-690,411,-464
+-384,-810,562
+-785,-685,-485
+-795,451,-566
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+-455,-767,470
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+-917,726,512
+-20,152,68
+-778,-675,-648
+-763,-609,-482
+509,416,-417
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+461,-602,572
+521,550,-310
+
+--- scanner 14 ---
+-322,-641,670
+-349,354,-648
+-625,714,619
+812,-715,-617
+-491,-748,669
+821,527,-792
+909,550,885
+-599,728,593
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+-46,-32,-48
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+896,-755,-710
+920,385,796
+861,469,-784
+-738,-741,-366
+-681,773,462
+
+--- scanner 15 ---
+-863,636,832
+887,603,374
+-66,-152,-18
+-406,-515,-665
+-501,-905,785
+542,-591,-441
+790,520,-691
+562,-667,653
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+-611,-836,857
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+-784,760,860
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+66,2,27
+-839,277,-736
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+-752,658,797
+-576,-505,-555
+-746,345,-682
+543,-455,-365
+851,590,554
+-399,-914,859
+436,-477,-381
+
+--- scanner 16 ---
+695,-489,-727
+-393,764,-274
+513,-404,724
+733,406,705
+788,-449,-811
+804,-386,-777
+-591,-456,576
+-715,-313,-340
+-544,907,364
+135,43,-46
+-534,924,338
+-559,835,455
+-315,762,-398
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+-693,-291,-340
+-378,843,-372
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+454,414,-693
+-604,-446,472
+-601,-248,-269
+465,460,-686
+-592,-563,407
+749,580,604
+76,148,91
+
+--- scanner 17 ---
+455,-760,-649
+670,-470,334
+569,454,608
+-358,-652,-715
+-522,413,-718
+578,-408,376
+-499,503,-639
+-510,818,236
+-465,-659,-734
+530,478,-610
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+-435,-673,316
+-123,-22,19
+-481,808,411
+630,-482,500
+-421,-818,-768
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+-573,-797,318
+-490,705,351
+-535,-547,309
+-502,454,-681
+385,-756,-759
+330,-731,-694
+20,-66,-142
+736,518,636
+522,517,683
+
+--- scanner 18 ---
+488,-495,-482
+753,833,793
+575,545,-722
+437,-478,-662
+-380,740,-476
+-589,-884,-619
+-447,-668,405
+512,-794,706
+66,67,-124
+-535,581,492
+-383,-610,455
+555,-671,789
+-392,808,-633
+-659,-782,-672
+-477,812,-495
+741,783,712
+-641,-817,-476
+721,728,746
+-433,523,401
+513,-605,602
+613,677,-617
+188,-120,-51
+-553,-645,460
+400,-493,-422
+-598,533,370
+546,787,-712
+
+--- scanner 19 ---
+680,468,656
+-895,-366,652
+-732,-787,-709
+-801,-610,-698
+451,-753,587
+600,-429,-518
+-808,-712,-655
+-85,174,-91
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+-787,899,-508
+-696,913,386
+-631,962,384
+-752,920,482
+499,-445,-344
+-864,885,-423
+-821,796,-468
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+56,66,25
+466,693,-633
+593,624,698
+715,682,633
+501,782,-567
+-897,-420,814
+459,-483,-564
+-883,-452,696
+
+--- scanner 20 ---
+397,-456,465
+822,541,-705
+-805,-570,-623
+484,-683,-391
+-592,793,-393
+-867,737,670
+-592,-860,531
+-506,805,-437
+-881,820,497
+-560,807,-275
+432,554,511
+-12,12,62
+780,662,-607
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+-893,-541,-502
+-503,-915,463
+330,-529,600
+408,439,440
+-715,-853,455
+-849,835,649
+542,-805,-456
+-129,-146,27
+-874,-471,-564
+
+--- scanner 21 ---
+533,528,-756
+635,945,504
+924,-707,-431
+926,-248,469
+-453,651,678
+743,907,422
+18,113,48
+-426,-601,-285
+-587,-409,730
+-602,-306,668
+934,-310,681
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+-219,-659,-318
+789,-634,-364
+-609,608,678
+-494,-457,635
+-602,695,664
+-672,954,-527
+-322,-639,-423
+
+--- scanner 22 ---
+665,-972,357
+157,-75,5
+-645,524,554
+-661,-821,715
+552,-766,-295
+572,402,640
+534,-897,368
+-544,439,-366
+-641,414,484
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+596,-852,-283
+-616,479,429
+-479,-856,715
+6,-31,124
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+434,-798,-281
+593,563,629
+-537,458,-259
+-703,405,-322
+-338,-477,-268
+-580,-849,831
+758,440,633
+569,-955,356
+528,455,-423
+-490,-509,-253
+-511,-491,-351
+
+--- scanner 23 ---
+388,-809,-352
+-367,872,532
+-415,-631,622
+743,-603,724
+-753,552,-643
+562,-642,690
+139,81,144
+451,-707,-384
+-381,-642,874
+383,456,849
+-411,-684,-537
+416,-685,-273
+-384,-613,831
+-338,776,398
+412,553,858
+399,591,733
+-264,869,422
+-733,574,-623
+-414,-599,-703
+674,-497,728
+48,-39,41
+389,865,-737
+-669,584,-587
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+-348,-718,-636
+391,787,-525
+
+--- scanner 24 ---
+-784,-392,606
+-484,366,661
+736,683,764
+-663,-858,-769
+833,-740,823
+-553,-789,-841
+821,-458,-849
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+-325,324,752
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+1,-137,118
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+-380,807,-844
+-301,683,-816
+-588,-458,571
+696,601,-489
+-412,705,-781
+-758,-468,681
+661,785,811
+
+--- scanner 25 ---
+500,-759,-543
+637,-476,865
+844,524,-809
+691,-401,789
+755,549,-692
+-670,-822,952
+680,-578,858
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+-536,581,-571
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+-738,485,812
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+-832,-768,954
+827,534,-783
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+-697,522,832
+-24,26,176
+-643,582,-740
+-484,-523,-423
+546,-705,-402
+-526,594,-675
+36,-123,83
+-648,564,835
+-714,-736,940
+311,819,948
+
+--- scanner 26 ---
+-609,-865,-696
+-730,-552,628
+320,796,-676
+-480,446,-760
+-789,-814,-679
+752,-686,698
+86,-103,-33
+-54,-53,105
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+-543,462,-794
+-688,-396,541
+312,517,722
+462,-422,-642
+426,-451,-511
+-557,806,840
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+-619,825,770
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+-849,-902,-681
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+-498,737,741
+444,-531,-542
+-665,-610,506
+323,826,-713
+-583,555,-710
+486,501,621
+
+--- scanner 27 ---
+440,-949,710
+-548,356,729
+-860,601,-538
+464,-767,-452
+653,723,873
+-846,-908,-728
+440,436,-892
+-730,-861,516
+4,-62,-113
+541,420,-718
+407,-702,-603
+581,741,842
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+-674,-844,415
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+-923,-894,-813
+-880,-805,-768
+-93,-141,27
+-550,496,745
+400,474,-672
+-571,298,738
+-615,-768,460
+-867,703,-581
+-791,778,-527
+406,-925,854
+
+--- scanner 28 ---
+647,354,627
+754,-710,818
+-32,-37,79
+-607,574,728
+706,-823,-325
+-440,806,-361
+811,-701,682
+-630,680,673
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+-604,-428,344
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+-907,-614,-778
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+-481,-385,427
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+-670,-386,531
+-794,-719,-842
+-418,699,-345
+
+--- scanner 29 ---
+345,-686,278
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+-10,-33,-90
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+-830,567,-808
+-329,-599,712
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+-454,-606,663
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+-520,-433,-570
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+-464,-557,820
+-121,76,13
+-599,-325,-596
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+
+--- scanner 30 ---
+898,-783,-440
+922,437,482
+-471,-599,844
+754,-763,593
+74,-14,20
+-699,-844,-819
+905,-782,548
+7,-163,-135
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+-386,-589,679
+427,680,-886
+405,573,-902
+-465,303,-496
+-661,-982,-715
+-477,-574,623
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+-719,-949,-922
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+
+--- scanner 31 ---
+246,-795,-450
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+-737,-654,-829
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+-748,371,-546
+-636,391,-522
+-451,-517,506
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+-33,-82,-118
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+-737,-472,-794
+-853,-553,-822
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+344,-589,466
+-506,-492,441
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+-469,691,760
+237,-596,485
+
+--- scanner 32 ---
+299,519,833
+-547,650,-617
+395,-426,414
+-954,-698,761
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+-715,929,492
+-555,612,-825
+-856,-676,911
+-911,-705,734
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+-657,-723,-474
+-658,986,590
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+-702,-598,-445
+-134,142,-43
+-587,540,-648
+239,648,792
+356,-436,487
+678,-437,-611
+-22,23,114
+271,842,-392
+
+--- scanner 33 ---
+353,649,717
+632,-572,-385
+627,-425,511
+569,-375,575
+-478,613,-778
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+-678,-709,356
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+-792,-285,-709
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+-31,148,10
+-849,-421,-700
+-565,571,-622
+-538,915,708
+443,-676,-384
+-719,-420,-776
\ No newline at end of file
diff --git a/19/solution.c b/19/solution.c
new file mode 100644
index 0000000..6f45173
--- /dev/null
+++ b/19/solution.c
@@ -0,0 +1,129 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+
+typedef struct beacon {
+    int x,y,z;
+} beacon;
+
+typedef struct scanner {
+    int nbeacons, known;
+    beacon *beacons;
+} scanner;
+
+inline static beacon transform(beacon b, int i) {
+    int x=b.x,y=b.y,z=b.z;
+#define r(n,a,b,c) case n: return (beacon){a,b,c}
+    switch (i) {
+        r( 0, x, y, z); r( 1, x,-y,-z); r( 2, x, z,-y); r( 3, x,-z, y);
+        r( 4, y, x,-z); r( 5, y,-x, z); r( 6, y, z, x); r( 7, y,-z,-x);
+        r( 8, z, x, y); r( 9, z,-x,-y); r(10, z, y,-x); r(11, z,-y, x);
+        r(12,-x, y,-z); r(13,-x,-y, z); r(14,-x, z, y); r(15,-x,-z,-y);
+        r(16,-y, x, z); r(17,-y,-x,-z); r(18,-y, z,-x); r(19,-y,-z, x);
+        r(20,-z, x,-y); r(21,-z,-x, y); r(22,-z, y, x); r(23,-z,-y,-x);
+    }
+    return (beacon){0};
+}
+
+inline static beacon sub(beacon a, beacon b) {
+    return (beacon){a.x-b.x, a.y-b.y, a.z-b.z};
+}
+
+inline static int manhattan(beacon a, beacon b) {
+    return abs(a.x-b.x) + abs(a.y-b.y) + abs(a.z-b.z);
+}
+
+int main() {
+    scanner *scanners=NULL;
+    beacon *known_beacons;
+    int nscanners, known=1,knownb=0;
+    getchar();
+
+    while(scanf("-- scanner %d ---\n",&nscanners)==1) {
+        nscanners++;
+        scanners=realloc(scanners,nscanners*sizeof(scanner));
+        scanner *s = &scanners[nscanners-1];
+        s->beacons=NULL;
+        s->nbeacons=1;
+        s->known=nscanners==1;
+        beacon b;
+        while(scanf("%i,%i,%i",&b.x,&b.y,&b.z)==3) {
+            s->beacons=realloc(s->beacons,++s->nbeacons*sizeof(beacon));
+            s->beacons[s->nbeacons-1]=b;
+            knownb++;
+        }
+        memset(&s->beacons[0],0,sizeof(beacon));
+        scanf("%*[^-]");
+    }
+
+    known_beacons = malloc(knownb*sizeof(beacon));
+    knownb = scanners[0].nbeacons;
+    memcpy(known_beacons, scanners[0].beacons, knownb*sizeof(beacon));
+
+    while (known<nscanners) {
+#pragma omp parallel for schedule(dynamic,10) collapse(2)
+        for (int i=0;i<nscanners;i++) {
+            for (int m=0;m<24;m++) {
+            if (scanners[i].known) continue;
+                for(int kb=0; kb<knownb; kb++) {
+                    for(int tp=1;tp<scanners[i].nbeacons;tp++) {
+                        int candidates=0;
+                        beacon disp = sub(transform(scanners[i].beacons[tp],m), known_beacons[kb]);
+                        for (int dp=1;dp<scanners[i].nbeacons;dp++) {
+                            beacon c = sub(transform(scanners[i].beacons[dp],m),disp);
+                            for (int ckb=0;ckb<knownb;ckb++) {
+                                if (!memcmp(&c, &known_beacons[ckb], sizeof(beacon))){
+                                    candidates++;
+                                    if (candidates >= 12) {
+#pragma omp critical
+{
+                                        beacon tmp[scanners[i].nbeacons-1];
+                                        int ntmp=0;
+                                        for (int kdp=1;kdp<scanners[i].nbeacons;kdp++) {
+                                            beacon t = sub(transform(scanners[i].beacons[kdp],m),disp);
+                                            int found=0;
+                                            for (int kdc=0;kdc<knownb;kdc++)
+                                                if (!memcmp(&t, &known_beacons[kdc],sizeof(beacon))) {
+                                                    found++;break;
+                                                }
+                                            if (!found)
+                                                tmp[ntmp++] = t;
+                                        }
+                                        memcpy(known_beacons+knownb,tmp,ntmp*sizeof(beacon));
+                                        knownb+=ntmp;
+
+                                        scanners[i].beacons[0] = (beacon){-disp.x,-disp.y,-disp.z};
+                                        scanners[i].known=1;
+                                        known++;
+                                        printf("%d/%d\n",known,nscanners);
+}
+                                        goto next;
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            next:
+            }
+        }
+    }
+    printf("Silver: %d\n",knownb-1);
+
+    int G=0;
+    for(int i=0;i<nscanners;i++){
+        for(int j=0;j<nscanners;j++) {
+            int m = manhattan(scanners[i].beacons[0],scanners[j].beacons[0]);
+            if (m > G) G=m;
+        }
+    }
+
+    printf("Gold: %d\n",G);
+
+    for(int i=0;i<nscanners;i++)
+        free(scanners[i].beacons);
+
+    free(scanners);
+    free(known_beacons);
+}