dumping 5 days of unrefined solutions :)

2022/day07/main.go

@@ -0,0 +1,168 @@
+package main
+
+import (
+	_ "embed"
+	"flag"
+	"fmt"
+	"math"
+	"strings"
+
+	"github.com/alexchao26/advent-of-code-go/cast"
+	"github.com/alexchao26/advent-of-code-go/mathy"
+	"github.com/alexchao26/advent-of-code-go/util"
+)
+
+//go:embed input.txt
+var input string
+
+func init() {
+	// do this in init (not main) so test file has same input
+	input = strings.TrimRight(input, "\n")
+	if len(input) == 0 {
+		panic("empty input.txt file")
+	}
+}
+
+func main() {
+	var part int
+	flag.IntVar(&part, "part", 1, "part 1 or 2")
+	flag.Parse()
+	fmt.Println("Running part", part)
+
+	if part == 1 {
+		ans := part1(input)
+		util.CopyToClipboard(fmt.Sprintf("%v", ans))
+		fmt.Println("Output:", ans)
+	} else {
+		ans := part2(input)
+		util.CopyToClipboard(fmt.Sprintf("%v", ans))
+		fmt.Println("Output:", ans)
+	}
+}
+
+func part1(input string) int {
+	root := parseInput(input)
+
+	return sumDirsUnder100000(root)
+}
+
+func sumDirsUnder100000(itr *dir) int {
+	SizeLimit := 100000
+
+	sum := 0
+	if itr.totalSize <= SizeLimit {
+		sum += itr.totalSize
+	}
+	for _, child := range itr.childDirs {
+		sum += sumDirsUnder100000(child)
+	}
+	return sum
+}
+
+func part2(input string) int {
+	root := parseInput(input)
+	totalSapceAvailable := 70000000
+	spaceNeeded := 30000000
+
+	// find smallest directory to be deleted that would free up enough space...
+	directoryMinSize := spaceNeeded - (totalSapceAvailable - root.totalSize)
+	return findSmallestDirToDelete(root, directoryMinSize)
+}
+
+func findSmallestDirToDelete(itr *dir, directoryMinSize int) int {
+	smallest := math.MaxInt64
+	if itr.totalSize >= directoryMinSize {
+		smallest = mathy.MinInt(smallest, itr.totalSize)
+	}
+
+	for _, childDirs := range itr.childDirs {
+		smallest = mathy.MinInt(smallest, findSmallestDirToDelete(childDirs, directoryMinSize))
+	}
+
+	return smallest
+}
+
+type dir struct {
+	name      string
+	parentDir *dir
+	childDirs map[string]*dir
+	files     map[string]int
+	totalSize int
+}
+
+func parseInput(input string) *dir {
+	root := &dir{
+		name:      "root",
+		childDirs: map[string]*dir{},
+	}
+	itr := root
+
+	cmds := strings.Split(input, "\n")
+	c := 0
+
+	for c < len(cmds) {
+		switch cmd := cmds[c]; cmd[0:1] {
+		case "$":
+			if cmd == "$ ls" {
+				// just move on, we will assume we're always in an listing state
+				c++
+			} else {
+				changeDir := strings.Split(cmd, "cd ")[1]
+				changeDir = strings.TrimSpace(changeDir)
+				if changeDir == ".." {
+					itr = itr.parentDir
+				} else {
+					// if changeDir doesn't exist..
+					if _, ok := itr.childDirs[changeDir]; !ok {
+						itr.childDirs[changeDir] = &dir{
+							name:      changeDir,
+							parentDir: itr,
+							childDirs: map[string]*dir{},
+							files:     map[string]int{}}
+					}
+
+					itr = itr.childDirs[changeDir]
+				}
+				c++
+			}
+		default:
+			// assume we're listing a dir's contents... add it
+			if strings.HasPrefix(cmd, "dir") {
+				childDirName := cmd[4:]
+				if _, ok := itr.childDirs[childDirName]; !ok {
+					itr.childDirs[childDirName] = &dir{
+						name:      childDirName,
+						parentDir: itr,
+						childDirs: map[string]*dir{},
+						files:     map[string]int{},
+					}
+				}
+			} else {
+				// file name
+				parts := strings.Split(cmd, " ")
+				itr.files[parts[0]] = cast.ToInt(parts[0])
+			}
+			c++
+		}
+	}
+
+	populateFileSizes(root)
+	return root
+}
+
+func populateFileSizes(itr *dir) int {
+	totalSize := 0
+
+	for _, childItr := range itr.childDirs {
+		totalSize += populateFileSizes(childItr)
+	}
+
+	for _, sz := range itr.files {
+		totalSize += sz
+	}
+
+	itr.totalSize = totalSize
+
+	return totalSize
+
+}

2022/day07/main_test.go

@@ -0,0 +1,81 @@
+package main
+
+import (
+	"testing"
+)
+
+var example = `$ cd /
+$ ls
+dir a
+14848514 b.txt
+8504156 c.dat
+dir d
+$ cd a
+$ ls
+dir e
+29116 f
+2557 g
+62596 h.lst
+$ cd e
+$ ls
+584 i
+$ cd ..
+$ cd ..
+$ cd d
+$ ls
+4060174 j
+8033020 d.log
+5626152 d.ext
+7214296 k`
+
+func Test_part1(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  int
+	}{
+		{
+			name:  "example",
+			input: example,
+			want:  95437,
+		},
+		{
+			name:  "actual",
+			input: input,
+			want:  1423358,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := part1(tt.input); got != tt.want {
+				t.Errorf("part1() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func Test_part2(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  int
+	}{
+		{
+			name:  "example",
+			input: example,
+			want:  24933642,
+		},
+		{
+			name:  "actual",
+			input: input,
+			want:  545729,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := part2(tt.input); got != tt.want {
+				t.Errorf("part2() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}