feat: add day 1 2024

aoc2024/day01/example.txt

@@ -0,0 +1,6 @@
+3   4
+4   3
+2   5
+1   3
+3   9
+3   3

aoc2024/day01/main.go

@@ -4,6 +4,9 @@ import (
 	"bufio"
 	_ "embed"
 	"fmt"
+	"iter"
+	"slices"
+	"sort"
 
 	aoc "go.sour.is/advent-of-code"
 )
@@ -20,11 +23,64 @@ type result struct {
 func (r result) String() string { return fmt.Sprintf("%#v", r) }
 
 func run(scan *bufio.Scanner) (*result, error) {
+	var (
+		left  []int
+		right []int
+	)
 
 	for scan.Scan() {
-		_ = scan.Text()
+		txt := scan.Text()
 
+		var l, r int
+		_, err := fmt.Sscanf(txt, "%d %d", &l, &r)
+		if err != nil {
+			return nil, err
+		}
+
+		left = append(left, l)
+		right = append(right, r)
 	}
 
-	return &result{}, nil
+	sort.Ints(left)
+	sort.Ints(right)
+
+	result := &result{}
+
+	result.valuePT1 = aoc.Reduce(func(i int, z pair[int, int], sum int) int {
+		return sum + aoc.ABS(z.L-z.R)
+	}, 0, zip(slices.Values(left), slices.Values(right)))
+
+	rmap := aoc.Reduce(func(i int, z int, m map[int]int) map[int]int {
+		m[z]++
+		return m
+	}, make(map[int]int), slices.Values(right))
+	
+	for _, v := range left {
+		if r, ok := rmap[v]; ok {	
+			result.valuePT2 += v*r
+		}
+	}
+
+	return result, nil
 }
+
+type pair[L, R any] struct {
+	L L
+	R R
+}
+
+func zip[L, R any](l iter.Seq[L], r iter.Seq[R]) iter.Seq[pair[L,R]] {
+	return func(yield func(pair[L, R]) bool) {
+		pullR, stop := iter.Pull(r)
+		defer stop()
+
+		for l := range l {
+			r, _ := pullR()
+
+			if !yield(pair[L, R]{L: l, R: r}) {
+				return
+			}
+		}
+	}
+}
+

aoc2024/day01/main_test.go

@@ -24,8 +24,8 @@ func TestExample(t *testing.T) {
 	is.NoErr(err)
 
 	t.Log(result)
-	is.Equal(result.valuePT1, 0)
+	is.Equal(result.valuePT1, 11)
-	is.Equal(result.valuePT2, 0)
+	is.Equal(result.valuePT2, 31)
 }
 
 func TestSolution(t *testing.T) {
@@ -36,6 +36,6 @@ func TestSolution(t *testing.T) {
 	is.NoErr(err)
 
 	t.Log(result)
-	is.Equal(result.valuePT1, 0)
+	is.Equal(result.valuePT1, 2756096)
-	is.Equal(result.valuePT2, 0)
+	is.Equal(result.valuePT2, 23117829)
 }