day24, example

day24/lines_test.go

@@ -0,0 +1,71 @@
+package day24
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestReadLine(t *testing.T) {
+	lines := `19, 13, 30 @ -2,  1, -2
+18, 19, 22 @ -1, -1, -2
+20, 25, 34 @ -2, -2, -4
+12, 31, 28 @ -1, -2, -1
+20, 19, 15 @  1, -5, -3`
+
+	for _, line := range strings.Split(lines, "\n") {
+		hail := ReadHailLine(line)
+		t.Log(hail)
+	}
+
+}
+
+func TestSecondPointIsInFuture(t *testing.T) {
+	lines := `19, 13, 30 @ -2,  1, -2
+18, 19, 22 @ -1, -1, -2
+20, 25, 34 @ -2, -2, -4
+12, 31, 28 @ -1, -2, -1
+20, 19, 15 @  1, -5, -3`
+
+	for _, line := range strings.Split(lines, "\n") {
+		hail := ReadHailLine(line)
+		t.Log(hail)
+		t.Logf("calced seconds point %+v is in future %t\n", hail.p1, hail.PointInFuture(hail.p1))
+	}
+
+}
+
+func TestIntersectExampleOne(t *testing.T) {
+	// Hailstone A: 19, 13, 30 @ -2, 1, -2
+	// Hailstone B: 18, 19, 22 @ -1, -1, -2
+	// Hailstones' paths will cross inside the test area (at x=14.333, y=15.333).
+
+	hA := ReadHailLine("19, 13, 30 @ -2, 1, -2")
+	hB := ReadHailLine("18, 19, 22 @ -1, -1, -2")
+
+	x, y, check := IntersectByTwoPoints(hA, hB)
+	if !check {
+		panic("should intersect")
+	}
+	t.Logf("got intersection at %f %f", x, y)
+}
+
+func TestIntersectExampleTwo(t *testing.T) {
+	// Hailstone A: 18, 19, 22 @ -1, -1, -2
+	// Hailstone B: 20, 25, 34 @ -2, -2, -4
+	hA := ReadHailLine("18, 19, 22 @ -1, -1, -2")
+	hB := ReadHailLine("20, 25, 34 @ -2, -2, -4")
+
+	x, y, check := IntersectByTwoPoints(hA, hB)
+	if check {
+		panic("should not intersect")
+	}
+	t.Logf("got intersection at %f %f", x, y)
+}
+
+func TestExamplePairwiseChecks(t *testing.T) {
+	filename := "example"
+	hails := ReadHailFile(filename)
+
+	intersections := CheckPairwiseIntersections(hails)
+	t.Log("counted intersections ", intersections)
+}