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package main
import (
"fmt"
"os"
"strings"
)
type Direction string
const (
Up Direction = "up"
Down Direction = "down"
Left Direction = "left"
Right Direction = "right"
TopLeft Direction = "topleft"
TopRight Direction = "topRight"
BottomLeft Direction = "botleft"
BottomRight Direction = "botRight"
)
func FileRead(path string) string {
file, err := os.ReadFile(path)
if err != nil {
fmt.Println("Couldn't Read file: ", err)
}
return string(file)
}
func parseInput(data string) []string {
return strings.Split(data, "\n")
}
func isValid(x int, y int, n int, m int) bool {
return x >= 0 && x < n && y >= 0 && y < m
}
func solve_part_one(data string) int {
grid := parseInput(data)
grid = grid[:len(grid)-1]
n := len(grid)
m := len(grid[0])
dx := [8]int{1, -1, 0, 0, 1, 1, -1, -1}
dy := [8]int{0, 0, 1, -1, 1, -1, 1, -1}
var words []string
for x := range len(grid) {
for y := range len(grid[0]) {
if grid[x][y] == byte('X') {
for i := range 8 {
word := "X"
for j := 1; j <= 3; j++ {
nx := x + dx[i]*j
ny := y + dy[i]*j
if isValid(nx, ny, n, m) {
word += string(grid[nx][ny])
}
words = append(words, word)
}
}
}
}
}
cnt := 0
for _, word := range words {
if word == "XMAS" {
cnt++
}
}
return cnt
}
func iSXMAS(window []string) bool {
patterns := [][]string{{"M.M",
".A.",
"S.S"}, {"M.S",
".A.",
"M.S"}, {"S.S",
".A.",
"M.M"}, {"S.M",
".A.",
"S.M"}}
for _, pat := range patterns {
flag := true
for i := range len(window) {
for j := range len(window[0]) {
if pat[i][j] != '.' {
flag = flag && (pat[i][j] == window[i][j])
}
}
}
if flag {
return true
}
}
return false
}
func solve_part_two(data string) int {
grid := parseInput(data)
grid = grid[:len(grid)-1]
n := len(grid)
m := len(grid[0])
var windows [][]string
for x := range n - 2 {
for y := range m - 2 {
var window []string
for i := range 3 {
window = append(window, grid[i+y][x:x+3])
}
windows = append(windows, window)
}
}
cnt := 0
// fmt.Println(windows)
for _, window := range windows {
if iSXMAS(window) {
cnt += 1
}
}
return cnt
}
func main() {
test := FileRead("../input/day4.test")
prod := FileRead("../input/day4.prod")
fmt.Println("Part_1 test: ", solve_part_one(test))
fmt.Println("Part_1 prod: ", solve_part_one(prod))
fmt.Println("Part_2 test: ", solve_part_two(test))
fmt.Println("Part_2 prod: ", solve_part_two(prod))
}
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