[Codetree] 체크판위에서 2

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int R = sc.nextInt();
        int C = sc.nextInt();
        char[][] grid = new char[R][C];
        for (int i = 0; i < R; i++) {
            for (int j = 0; j < C; j++) {
                grid[i][j] = sc.next().charAt(0);
            }
        }
        
        int cnt = 0;
        
        for(int i = 1; i < R; i++) {
            for(int j = 1; j < C; j++) {
                for(int k = i+1; k < R - 1; k++) {
                    for(int l = j + 1; l < C - 1; l++) {
                        if(grid[0][0]!=grid[i][j] && 
                            grid[i][j]!=grid[k][l] &&
                            grid[k][l]!=grid[R-1][C-1]
                        ) {
                        cnt++;
                        }
                    }
                }
            }
        }
        System.out.println(cnt);
    }
}

import java.util.Scanner;

public class Main {
    public static int cnt = 0;
    static char[][] grid;
    static int R,C;
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        R = sc.nextInt();
        C = sc.nextInt();         
        grid = new char[R][C];
        for (int i = 0; i < R; i++) {
            for (int j = 0; j < C; j++) {
                grid[i][j] = sc.next().charAt(0);
            }
        }

        dfs(0, 0, grid[0][0], 0);
        System.out.println(cnt);
    }
    public static void dfs(int y, int x, char prev, int depth) {
        if(depth > 2) return;
        if(depth == 2) {
            if(y < R-1 && x < C-1 && grid[R-1][C-1] != prev) cnt++;        
        }
        
        for(int i = y + 1; i < R; i++) {
            for(int j = x + 1; j < C; j++) {
                if(grid[i][j] != prev) {
                    dfs(i, j, grid[i][j], depth+1);
                }
            }
        }
    }
}