dumping 5 days of unrefined solutions :)

2022/day14/main.go

@@ -0,0 +1,189 @@
+package main
+
+import (
+	_ "embed"
+	"flag"
+	"fmt"
+	"math"
+	"sort"
+	"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 {
+	matrix := parseInput(input)
+	originCol := 0
+	for i, c := range matrix[0] {
+		if c == "+" {
+			originCol = i
+		}
+	}
+
+	ans := 0
+	for !dropSand(matrix, originCol) {
+		ans++
+	}
+
+	return ans
+}
+
+func part2(input string) int {
+	matrix := parseInput(input)
+	originCol := 0
+	for i, c := range matrix[0] {
+		if c == "+" {
+			originCol = i
+		}
+		matrix[len(matrix)-1][i] = "#"
+	}
+
+	ans := 0
+	for !dropSand(matrix, originCol) {
+		ans++
+		// COULD incorporate this into the for loop conditional but then the
+		// ordering is important... must check origin cell BEFORE running
+		// dropSand... it's easier to read here...
+		if matrix[0][originCol] == "o" {
+			break
+		}
+	}
+
+	return ans
+}
+
+func parseInput(input string) (matrix [][]string) {
+	coordSets := [][][2]int{}
+	lowestCol := math.MaxInt64
+	highestRow := 0
+	for _, line := range strings.Split(input, "\n") {
+		rawCoords := strings.Split(line, " -> ")
+		coords := [][2]int{}
+		for _, rawCoord := range rawCoords {
+			rawNums := strings.Split(rawCoord, ",")
+			col, row := cast.ToInt(rawNums[0]), cast.ToInt(rawNums[1])
+			coord := [2]int{
+				col, row,
+			}
+			coords = append(coords, coord)
+
+			lowestCol = mathy.MinInt(lowestCol, col)
+			highestRow = mathy.MaxInt(highestRow, row)
+		}
+		coordSets = append(coordSets, coords)
+	}
+
+	// lowering this number to 1 makes it easier to print the matrix, which I
+	// used for part 1... but then needed to up it for part 2... or just have a
+	// massive screen and make the terminal text tiny...
+	ExtraLeftSpace := 200
+
+	highestCol := 0
+	for s, set := range coordSets {
+		for i := range set {
+			coordSets[s][i][0] -= lowestCol - ExtraLeftSpace
+			highestCol = mathy.MaxInt(highestCol, coordSets[s][i][0])
+		}
+	}
+
+	matrix = make([][]string, highestRow+3)
+	for r := range matrix {
+		matrix[r] = make([]string, highestCol+ExtraLeftSpace*2)
+	}
+
+	for _, set := range coordSets {
+		for i := 1; i < len(set); i++ {
+			cols := []int{set[i-1][0], set[i][0]}
+			rows := []int{set[i-1][1], set[i][1]}
+
+			sort.Ints(cols)
+			sort.Ints(rows)
+
+			if cols[0] == cols[1] {
+				for r := rows[0]; r <= rows[1]; r++ {
+					matrix[r][cols[0]] = "#"
+				}
+			} else if rows[0] == rows[1] {
+				for c := cols[0]; c <= cols[1]; c++ {
+					matrix[rows[0]][c] = "#"
+				}
+			}
+		}
+	}
+
+	originCol := 500 - lowestCol + ExtraLeftSpace
+	// make it a plus so it's searchable in the next step... or could just
+	// return this value too...
+	matrix[0][originCol] = "+"
+
+	for i, r := range matrix {
+		for j := range r {
+			if matrix[i][j] == "" {
+				matrix[i][j] = "."
+			}
+		}
+	}
+
+	// printMatrix(matrix)
+	return matrix
+}
+
+func printMatrix(matrix [][]string) {
+	for _, r := range matrix {
+		fmt.Println(r)
+	}
+}
+
+func dropSand(matrix [][]string, originCol int) (fallsIntoAbyss bool) {
+	r, c := 0, originCol
+
+	for r < len(matrix)-1 {
+		below := matrix[r+1][c]
+		diagonallyLeft := matrix[r+1][c-1]
+		diagonallyRight := matrix[r+1][c+1]
+		if below == "." {
+			r++
+		} else if diagonallyLeft == "." {
+			r++
+			c--
+		} else if diagonallyRight == "." {
+			r++
+			c++
+		} else {
+			matrix[r][c] = "o"
+			return false
+		}
+	}
+
+	return true
+}