Day 6

2023/gareth/day01/day01.go

@@ -1,61 +0,0 @@
-package day01
-
-import (
-	"regexp"
-	"strconv"
-	"strings"
-)
-
-func Part1(input string) int {
-	total := 0
-	lines := strings.Split(input, "\r\n")
-	for _, line := range lines {
-		regex := regexp.MustCompile("[a-zA-Z]")
-		numbers := regex.ReplaceAllString(line, "")
-		number := string(numbers[0]) + string(numbers[len(numbers)-1])
-		i, _ := strconv.Atoi(number)
-		total += i
-	}
-
-	return total
-}
-
-func Part2(input string) int {
-	values := map[string]string{
-		"one":   "1",
-		"two":   "2",
-		"three": "3",
-		"four":  "4",
-		"five":  "5",
-		"six":   "6",
-		"seven": "7",
-		"eight": "8",
-		"nine":  "9",
-	}
-	lines := strings.Split(input, "\r\n")
-	s := ""
-
-	total := 0
-	for _, line := range lines {
-		numbers := []string{}
-		for _, c := range line {
-			s = s + string(c)
-			if num, err := strconv.Atoi(string(c)); err == nil {
-				numbers = append(numbers, strconv.Itoa(num))
-				s = ""
-			}
-			for key, value := range values {
-				if strings.Contains(s, key) {
-					numbers = append(numbers, value)
-					buffer := s[len(s)-1]
-					s = "" + string(buffer)
-				}
-			}
-		}
-		number := numbers[0] + numbers[len(numbers)-1]
-		i, _ := strconv.Atoi(number)
-		total += i
-		s = ""
-	}
-	return total
-}

2023/gareth/day01/day01_test.go

@@ -1,25 +0,0 @@
-package day01
-
-import (
-	"github.com/stretchr/testify/assert"
-	"testing"
-)
-
-func TestPart1(t *testing.T) {
-	r := Part1(`1abc2
-pqr3stu8vwx
-a1b2c3d4e5f
-treb7uchet`)
-	assert.Equal(t, 142, r)
-}
-
-func TestPart2(t *testing.T) {
-	r := Part2(`two1nine
-eightwothree
-abcone2threexyz
-xtwone3four
-4nineeightseven2
-zoneight234
-7pqrstsixteen`)
-	assert.Equal(t, 281, r)
-}

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)
+}