with open("input.txt") as f:
    grid = [i.split() for i in f.readlines()]

#for line in grid:
    #print(line)

def maxRegion(grid):
    max_cell_counter = 0
    for row in range(len(grid)):
        for col in range(len(grid[0])):
            if grid[row][col] == 'Y':
                region_cell_count = count_region_cells(grid, row, col)
                max_cell_counter = max(max_cell_counter, region_cell_count)
    return max_cell_counter


def count_region_cells(grid, row, col):
    # if out of bounds
    if any([row < 0, col < 0, row >= len(grid), col >= len(grid[0])]):
        return 0
    
    # if already visited
    if grid[row][col] == 0 or grid[row][col] == "N":
        return 0
    
    cell_count = 1
    grid[row][col] = 0    # marking as visited
    
    for r in range(row - 1, row + 2):
        for c in range(col - 1, col + 2):
            if r == row and c == col:
                continue
            cell_count += count_region_cells(grid, r, c)
    return cell_count

print(maxRegion(grid))