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|
package main
import (
"fmt"
"os"
"sort"
"strings"
)
func FileRead(path string) string {
file, err := os.ReadFile(path)
if err != nil {
fmt.Println("Couldn't Read file: ", err)
}
return string(file)
}
type Grid = [][]rune
func printGrid(grid [][]rune) {
for _, row := range grid {
for _, cell := range row {
fmt.Print(string(cell))
}
fmt.Println()
}
}
func parseInput(data string) Grid {
lines := strings.Split(data, "\n")
var grid Grid
for _, line := range lines {
if len(line) > 0 {
runes := []rune(line)
grid = append(grid, runes)
}
}
return grid
}
func inBounds(x, y, n, m int) bool {
return x >= 0 && x < n && y >= 0 && y < m
}
func abs(x, y int) int {
if x-y < 0 {
return -(x - y)
} else {
return x - y
}
}
func bfs(grid Grid, start Point, seen *map[Point]bool) (int, int) {
perimeter := 1
area := 0
w, h := len(grid), len(grid[0])
var queue []Point
(*seen)[start] = true
queue = append(queue, start)
dx := []int{1, -1, 0, 0} // down, up, right, left
dy := []int{0, 0, 1, -1}
for len(queue) > 0 {
curPoint := queue[0]
curPlant := grid[curPoint[0]][curPoint[1]]
queue = queue[1:]
for i := 0; i < 4; i++ {
nx := curPoint[0] + dx[i]
ny := curPoint[1] + dy[i]
newPoint := Point{nx, ny}
if inBounds(nx, ny, w, h) && grid[nx][ny] == curPlant {
if !(*seen)[newPoint] {
perimeter++
queue = append(queue, newPoint)
(*seen)[newPoint] = true
}
} else {
area++
}
}
}
return perimeter, area
}
func getDir(dx, dy int) string {
if dx == 0 && dy == 1 {
return "R"
} else if dx == 0 && dy == -1 {
return "L"
} else if dx == -1 && dy == 0 {
return "U"
} else if dx == 1 && dy == 0 {
return "D"
}
return "unreachable"
}
func merge(walls [][4]int, dir int) int {
cnt := 0
for i := 0; i < len(walls)-1; i++ {
cur := walls[i]
next := walls[i+1]
if dir == 0 { // x direction
if cur[0] == next[0] && abs(cur[1], next[1]) == 1 && cur[2] == next[2] && cur[3] == next[3] {
cnt++
}
} else if dir == 1 { // y direction
if cur[1] == next[1] && abs(cur[0], next[0]) == 1 && cur[2] == next[2] && cur[3] == next[3] {
cnt++
} else {
}
}
}
return cnt
}
func printWalls(walls [][4]int) {
for _, wall := range walls {
fmt.Printf("(%d, %d) - %s / ", wall[0], wall[1], getDir(wall[2], wall[3]))
}
fmt.Println()
}
func bfs2(grid Grid, start Point, seen *map[Point]bool) (int, int) {
perimeter := 1
area := 0
w, h := len(grid), len(grid[0])
var queue []Point
var walls [][4]int
pointsX := make(map[int]map[Point]struct{})
pointsX[start[0]] = make(map[Point]struct{})
pointsX[start[0]][start] = struct{}{}
(*seen)[start] = true
queue = append(queue, start)
dx := []int{1, -1, 0, 0} // down, up, right, left
dy := []int{0, 0, 1, -1}
for len(queue) > 0 {
curPoint := queue[0]
curPlant := grid[curPoint[0]][curPoint[1]]
queue = queue[1:]
for i := 0; i < 4; i++ {
nx := curPoint[0] + dx[i]
ny := curPoint[1] + dy[i]
newPoint := Point{nx, ny}
if inBounds(nx, ny, w, h) && grid[nx][ny] == curPlant {
if !(*seen)[newPoint] {
perimeter++
queue = append(queue, newPoint)
(*seen)[newPoint] = true
}
} else {
area++
walls = append(walls, [4]int{curPoint[0], curPoint[1], dx[i], dy[i]})
if _, exists := pointsX[newPoint[0]]; !exists {
pointsX[newPoint[0]] = make(map[Point]struct{})
}
pointsX[newPoint[0]][newPoint] = struct{}{}
}
}
}
sort.Slice(walls, func(i, j int) bool {
if walls[i][0] != walls[j][0] {
return walls[i][0] < walls[j][0] // Sort by the first element
}
if walls[i][2] != walls[j][2] {
return walls[i][2] < walls[j][2] // Sort by the third element
}
if walls[i][3] != walls[j][3] {
return walls[i][3] < walls[j][3] // Sort by the third element
}
return walls[i][1] < walls[j][1] // Sort by the second element
})
area -= merge(walls, 0)
sort.Slice(walls, func(i, j int) bool {
if walls[i][1] != walls[j][1] {
return walls[i][1] < walls[j][1] // Sort by the second element
}
if walls[i][2] != walls[j][2] {
return walls[i][2] < walls[j][2] // If second is equal, sort by the third element
}
if walls[i][3] != walls[j][3] {
return walls[i][3] < walls[j][3]
|
