Attempted, but I definitely misunderstood something

04/code.go

@@ -0,0 +1,86 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+)
+
+func readInput(file *os.File) [][]byte {
+	scanner := bufio.NewScanner(file)
+	var matrix [][]byte
+
+	for scanner.Scan() {
+		line := scanner.Text()
+		if line == "" {
+			break
+		}
+
+		matrix = append(matrix, []byte(line))
+	}
+
+	return matrix
+}
+
+func countWordOccurrences(matrix [][]byte, word string) int {
+	rows, cols := len(matrix), len(matrix[0])
+	count := 0
+	found := make(map[string]bool)
+
+	var dfs func(i, j, wordIndex int, wordSoFar string)
+	dfs = func(i, j, wordIndex int, wordSoFar string) {
+		// Base case: we've matched all characters of the word
+		if wordIndex == len(word) {
+			if !found[wordSoFar] {
+				found[wordSoFar] = true
+				count++
+			}
+
+			return
+		}
+
+		// Check if the current position is valid
+		if i < 0 || i >= rows || j < 0 || j >= cols || matrix[i][j] != word[wordIndex] {
+			return
+		}
+
+		wordSoFar = fmt.Sprintf("%s%d_%d%c", wordSoFar, i, j, matrix[i][j])
+
+		// Move to the next character in the word
+		dfs(i+1, j, wordIndex+1, wordSoFar)   // Down
+		dfs(i-1, j, wordIndex+1, wordSoFar)   // Up
+		dfs(i, j+1, wordIndex+1, wordSoFar)   // Right
+		dfs(i, j-1, wordIndex+1, wordSoFar)   // Left
+		dfs(i+1, j+1, wordIndex+1, wordSoFar) // Diagonal down-right
+		dfs(i-1, j-1, wordIndex+1, wordSoFar) // Diagonal up-left
+		dfs(i+1, j-1, wordIndex+1, wordSoFar) // Diagonal down-left
+		dfs(i-1, j+1, wordIndex+1, wordSoFar) // Diagonal up-right
+	}
+
+	// Try each cell as a starting point
+	for i := 0; i < rows; i++ {
+		for j := 0; j < cols; j++ {
+			if matrix[i][j] == word[0] {
+				dfs(i, j, 0, "")
+			}
+		}
+	}
+	fmt.Println(found)
+	return count
+}
+
+func main() {
+	if len(os.Args) < 2 {
+		log.Fatal("You need to specify a file!")
+	}
+
+	filePath := os.Args[1]
+	file, err := os.Open(filePath)
+	if err != nil {
+		log.Fatalf("Failed to open %s!\n", filePath)
+	}
+
+	matrix := readInput(file)
+	fmt.Println("Part1:", countWordOccurrences(matrix, "XMAS"))
+}