package main

import (
	"bufio"
	"fmt"
	"log"
	"os"
)

func main() {
	f, err := os.Open("input")
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()

	sc := bufio.NewScanner(f)
	fmt.Println(xmasCnt(parseInput(sc)))
}

func parseInput(sc *bufio.Scanner) [][]rune {
	var data [][]rune
	for sc.Scan() {
		row := make([]rune, 0, 140)
		for _, ch := range sc.Text() {
			row = append(row, ch)
		}
		data = append(data, row)
	}
	return data
}

// START PART 1
func xmasCnt(data [][]rune) int {
	cnt := 0
	for i := range data {
		for j := range data[i] {
			coords := [...][8]int{
				{i, j, i+1, j, i+2, j, i+3, j},       // Vertical;   top-down
				{i, j, i-1, j, i-2, j, i-3, j},       // Vertical;   down-top
				{i, j, i, j+1, i, j+2, i, j+3},       // Horizontal; left-right
				{i, j, i, j-1, i, j-2, i, j-3},       // Horizontal; left-right
				{i, j, i-1, j+1, i-2, j+2, i-3, j+3}, // Diagonal; bl-tr
				{i, j, i+1, j+1, i+2, j+2, i+3, j+3}, // Diagonal; tl-br
				{i, j, i+1, j-1, i+2, j-2, i+3, j-3}, // Diagonal; tr-bl
				{i, j, i-1, j-1, i-2, j-2, i-3, j-3}, // Diagonal; br-tl
			}
			for _, x := range coords {
				if x[0] >= 0 && x[0] < len(data) &&
				x[2] >= 0 && x[2] < len(data) &&
				x[4] >= 0 && x[4] < len(data) &&
				x[6] >= 0 && x[6] < len(data) &&
				x[1] >= 0 && x[1] < len(data[0]) &&
				x[3] >= 0 && x[3] < len(data[0]) &&
				x[5] >= 0 && x[5] < len(data[0]) &&
				x[7] >= 0 && x[7] < len(data[0]) &&
				data[x[0]][x[1]] == 'X' &&
				data[x[2]][x[3]] == 'M' &&
				data[x[4]][x[5]] == 'A' &&
				data[x[6]][x[7]] == 'S' {
					cnt++
				}
			}
		}
	}
	return cnt
}
// END PART 1 START PART 2
func xmasCnt(data [][]rune) int {
	cnt := 0
	for i := range data {
		for j := range data[i] {
			if data[i][j] != 'A' ||
			i == 0 || i == len(data) - 1 ||
			j == 0 || j == len(data[0]) - 1 {
				continue
			}
			x1 := []rune{data[i-1][j-1], data[i+1][j+1]}
			x2 := []rune{data[i+1][j-1], data[i-1][j+1]}
			if (((x1[0] == 'S' && x1[1] == 'M') || (x1[0] == 'M' && x1[1] == 'S')) &&
			    ((x2[0] == 'S' && x2[1] == 'M') || (x2[0] == 'M' && x2[1] == 'S'))) {
				cnt++
			}
		}
	}
	return cnt
}
// END PART 2