Day 6

2023/gareth/day06/day06.go

@@ -0,0 +1,40 @@
+package day06
+
+type Race struct {
+	Time     int
+	Distance int
+}
+
+func Part1(input string) int {
+	var Races []Race
+	Races = append(Races, Race{56, 546})
+	Races = append(Races, Race{97, 1927})
+	Races = append(Races, Race{78, 1131})
+	Races = append(Races, Race{75, 1139})
+
+	total := 1
+	for _, r := range Races {
+		halfTime := r.Time / 2
+		for i := 0; i <= halfTime; i++ {
+			raceDis := i * (r.Time - i)
+			if raceDis > r.Distance {
+				total = total * (r.Time - (i * 2) + 1)
+				break
+			}
+		}
+	}
+	return total
+}
+
+func Part2(input string) int {
+	r := Race{56977875, 546192711311139}
+	halfTime := r.Time / 2
+	for i := 0; i <= halfTime; i++ {
+		raceDis := i * (r.Time - i)
+		if raceDis > r.Distance {
+			return r.Time - (i * 2) + 1
+
+		}
+	}
+	return -1
+}

2023/gareth/day06/day06_test.go

@@ -0,0 +1,16 @@
+package day06
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestPart1(t *testing.T) {
+	r := Part1(``)
+	assert.Equal(t, 1624896, r)
+}
+
+func TestPart2(t *testing.T) {
+	r := Part2(``)
+	assert.Equal(t, 32583852, r)
+}