feat(2023-05): initial brute force

angch/2023-05/main.go

@@ -0,0 +1,126 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+)
+
+type Range struct {
+	Dst   int
+	Src   int
+	Range int
+}
+type Records []Range
+type MapRecord struct {
+	From    string
+	To      string
+	Records Records
+}
+
+func (r *Records) Translate(i int) int {
+	for _, v := range *r {
+		// log.Println("Check", v.Src, v.Src+v.Range, i)
+		if i >= v.Src && i < v.Src+v.Range {
+			return v.Dst + i - v.Src
+		}
+	}
+	return i
+}
+
+func findLocation(maps map[string]MapRecord, v int) int{
+	curType := "seed"
+	for curType != "location" {
+		// fmt.Printf("%s %d, ", curType, v)
+		r := maps[curType].Records
+		v = r.Translate(v)
+		curType = maps[curType].To
+	}
+	return v
+	// fmt.Printf("%s %d, ", curType, v)
+	// fmt.Println()
+}
+
+func day5(file string) (part1, part2 int) {
+	f, _ := os.Open(file)
+	defer f.Close()
+	scanner := bufio.NewScanner(f)
+
+	seeds := []int{}
+	maps := make(map[string]MapRecord)
+	scanner.Scan()
+	t := scanner.Text()
+	for _, v := range strings.Fields(t) {
+		if v != "seeds:" {
+			a, err := strconv.Atoi(v)
+			if err == nil {
+				seeds = append(seeds, a)
+			}
+		}
+	}
+
+	for scanner.Scan() {
+		t := scanner.Text()
+		if strings.HasSuffix(t, " map:") {
+			t = strings.TrimSuffix(t, " map:")
+			from, to, ok := strings.Cut(t, "-to-")
+			if !ok {
+				continue
+			}
+			r := Records{}
+			for scanner.Scan() {
+				t := scanner.Text()
+				if t == "" {
+					break
+				}
+				rng := Range{}
+				fmt.Sscanf(t, "%d %d %d", &rng.Dst, &rng.Src, &rng.Range)
+				r = append(r, rng)
+			}
+			// log.Printf("%+v\n", r)
+			maps[from] = MapRecord{
+				From:    from,
+				To:      to,
+				Records: r,
+			}
+		}
+	}
+	_ = maps
+
+	lowest := -1
+	for _, v := range seeds {
+		v  =findLocation(maps, v)
+		if lowest == -1 || v < lowest {
+			lowest = v
+		}
+		// log.Println(lowest)
+	}
+	part1 = lowest
+
+	lowest = -1
+	for i := 0; i < len(seeds); i+=2 {
+		start := seeds[i]
+		rng := seeds[i+1]
+		for j := start; j < start+rng; j++ {
+			v := findLocation(maps, j)
+			if lowest == -1 || v < lowest {
+				lowest = v
+			}
+		}
+	}
+	part2 = lowest
+
+	return
+}
+
+func main() {
+	log.SetFlags(log.Lshortfile | log.LstdFlags)
+	part1, part2 := day5("test.txt")
+	if part1 != 35 || part2 != 46 {
+		log.Fatal("Test failed ", part1, part2)
+	}
+	fmt.Println(day5("input.txt"))
+}

angch/2023-05/test.txt

@@ -0,0 +1,33 @@
+seeds: 79 14 55 13
+
+seed-to-soil map:
+50 98 2
+52 50 48
+
+soil-to-fertilizer map:
+0 15 37
+37 52 2
+39 0 15
+
+fertilizer-to-water map:
+49 53 8
+0 11 42
+42 0 7
+57 7 4
+
+water-to-light map:
+88 18 7
+18 25 70
+
+light-to-temperature map:
+45 77 23
+81 45 19
+68 64 13
+
+temperature-to-humidity map:
+0 69 1
+1 0 69
+
+humidity-to-location map:
+60 56 37
+56 93 4