private void floodFill(char[][] mapa, int[][] numMap, int i, int j, int m,
            int n, int num) {

        numMap[i][j] = num;
        for (int k = i - 1; k <= i + 1; k++) {
            for (int l = j - 1; l <= j + 1; l++) {
                if (k >= 0 && k < m && l >= 0 && l < n && mapa[k][l] == '@'
                        && numMap[k][l] == 0) {
                    this.floodFill(mapa, numMap, k, l, m, n, num);
                }
            }
        }
    }