advent-of-code-go/2021/day19/main_test.go

package main

import (
	_ "embed"
	"testing"
)

// 0 and 1 overlap
// scanner 1 must be at 68,-1246,-43 (relative to scanner 0)
// 1 and 4 overlap, scanner 4 is at -20,-1133,1061 (relative to scanner 0)
// scanner 2 must be at 1105,-1205,1229 (relative to scanner 0) and scanner 3 must be at -92,-2380,-20 (relative to scanner 0
var example = `--- 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`

func Test_part1(t *testing.T) {
	tests := []struct {
		name   string
		input  string
		want1  int
		want2  int
		isLong bool
	}{
		{
			name:  "example",
			input: example,
			want1: 79,   // total number of beacons
			want2: 3621, // manhattan distance
		},
		{
			name:   "actual",
			input:  input,
			want1:  408,
			want2:  13348,
			isLong: true,
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			/*
				// could use testing.Short() and run via go test -v -short
				if testing.Short() {
					t.Skip("reason")
				}
			*/
			if testing.Short() {
				t.Skip("Skipping long test, 2021/day19, O(n^ALOT)")
			} else if tt.isLong {
				t.Log("WARNING: Running very slow tests for 2021/day19. Disable with -short testing flag")
			}
			got1, got2 := part1(tt.input)
			if got1 != tt.want1 {
				t.Errorf("part1() = %v, want %v", got1, tt.want1)
			}
			if got1 != tt.want1 {
				t.Errorf("part2() = %v, want %v", got2, tt.want2)
			}
		})
	}
}

var allTheSameScanner = `--- scanner 0 ---
-1,-1,1
-2,-2,2
-3,-3,3
-2,-3,1
5,6,-4
8,0,7

--- scanner 0 ---
1,-1,1
2,-2,2
3,-3,3
2,-1,3
-5,4,-6
-8,-7,0

--- scanner 0 ---
-1,-1,-1
-2,-2,-2
-3,-3,-3
-1,-3,-2
4,6,5
-7,0,8

--- scanner 0 ---
1,1,-1
2,2,-2
3,3,-3
1,3,-2
-4,-6,5
7,0,8

--- scanner 0 ---
1,1,1
2,2,2
3,3,3
3,1,2
-6,-4,-5
0,7,-8`

func Test_fillRotations(t *testing.T) {
	// using a table test but there is only one case (a given example)
	tests := []struct {
		name  string
		input string
	}{
		{input: allTheSameScanner},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			scanners := parseInput(tt.input)
			firstScanner := scanners[0]
			// create rotations of the first scanner
			firstScanner.fillRotations()

			// faster lookup for checking if all the original scanners are in the created rotations
			rotationMaps := []map[[3]int]bool{}
			for _, r := range firstScanner.rotations {
				m := map[[3]int]bool{}
				for _, c := range r {
					m[c] = true
				}
				rotationMaps = append(rotationMaps, m)
			}

			for i, scanner := range scanners {
				oneMapMatches := false
				for _, m := range rotationMaps {
					if !oneMapMatches {
						allFound := true
						for _, c := range scanner.relativeCoords {
							if !m[c] {
								allFound = false
							}
						}
						if allFound {
							oneMapMatches = true
						}
					}
				}

				if !oneMapMatches {
					t.Errorf("scanner with index %d is not within createRotations() result", i)
				}
			}
		})
	}
}