#!/usr/bin/env python3
# from typing import *

import sys
import io
import math
import collections
import decimal
import itertools
import bisect
import heapq


def input():
    return sys.stdin.readline()[:-1]


# sys.setrecursionlimit(1000000)

# _INPUT = """# paste here...
# """
# sys.stdin = io.StringIO(_INPUT)

class Dinic:
    def __init__(self, n):
        self.n = n
        self.links = [[] for _ in range(n)]
        self.depth = None
        self.progress = None
 
    def add_link(self, _from, to, cap):
        self.links[_from].append([cap, to, len(self.links[to])])
        self.links[to].append([0, _from, len(self.links[_from]) - 1])
 
    def bfs(self, s):
        depth = [-1] * self.n
        depth[s] = 0
        q = collections.deque([s])
        while q:
            v = q.popleft()
            for cap, to, rev in self.links[v]:
                if cap > 0 and depth[to] < 0:
                    depth[to] = depth[v] + 1
                    q.append(to)
        self.depth = depth
 
    def dfs(self, v, t, flow):
        if v == t:
            return flow
        links_v = self.links[v]
        for i in range(self.progress[v], len(links_v)):
            self.progress[v] = i
            cap, to, rev = link = links_v[i]
            if cap == 0 or self.depth[v] >= self.depth[to]:
                continue
            d = self.dfs(to, t, min(flow, cap))
            if d == 0:
                continue
            link[0] -= d
            self.links[to][rev][0] += d
            return d
        return 0
 
    def max_flow(self, s, t):
        flow = 0
        while True:
            self.bfs(s)
            if self.depth[t] < 0:
                return flow
            self.progress = [0] * self.n
            current_flow = self.dfs(s, t, INF)
            while current_flow > 0:
                flow += current_flow
                current_flow = self.dfs(s, t, INF)

INF = 10**10

H, W = map(int, input().split())
S = [input() for _ in range(H)]

# 2分グラフ: S -> (W) -> (B) -> T
mf = Dinic(H*W+2)
n_w, n_b = 0, 0
for h in range(H):
    for w in range(W):
        if S[h][w] == 'w':
            n_w += 1
            mf.add_link(0, h*W+w+1, 1)
            if 0 < w and S[h][w-1] != '.':
                mf.add_link(h*W+w+1, h*W+(w-1)+1, 1)
            if w < W-1 and S[h][w+1] != '.':
                mf.add_link(h*W+w+1, h*W+(w+1)+1, 1)
            if 0 < h and S[h-1][w] != '.':
                mf.add_link(h*W+w+1, (h-1)*W+w+1, 1)
            if h < H-1 and S[h+1][w] != '.':
                mf.add_link(h*W+w+1, (h+1)*W+w+1, 1)
        elif S[h][w] == 'b':
            n_b += 1
            mf.add_link(h*W+w+1, H*W+1, 1)

flow = mf.max_flow(0, H*W+1)
n_w -= flow
n_b -= flow
m = min(n_w, n_b)
score = flow*100 + m*10 + (n_w-m) + (n_b-m)
print(score)