import sys
sys.setrecursionlimit(10**6)
from collections import defaultdict

def dfs(v, t, f, used):
    if v == t:
        return f
    
    used[v] = True
    
    for nn, cap in edges[v].items():
        if not used[nn] and cap > 0:
            d = dfs(nn, t, min(f, cap), used)
            
            if d > 0:
                edges[v][nn] -= d
                edges[nn][v] += d
                
                return d
    
    return 0
    
def max_flow(s, t):
    flow = 0
    
    while True:
        used = [False] * (N*M+2)
        f = dfs(s, t, 10**18, used)
        
        if f == 0:
            return flow
            
        flow += f

N, M = map(int, input().split())
S = [input() for _ in range(N)]
edges = defaultdict(dict)
wc, bc = 0, 0

for i in range(N):
    for j in range(M):
        if S[i][j] == 'w':
            wc += 1
            edges[0][M*i+j+1] = 1
            edges[M*i+j+1][0] = 0
            
            for ni, nj in [(i-1, j), (i+1, j), (i, j-1), (i, j+1)]:
                if 0<=ni<N and 0<=nj<M and S[ni][nj] != '.':
                    edges[M*i+j+1][M*ni+nj+1] = 1
                    edges[M*ni+nj+1][M*i+j+1] = 0
        
        if S[i][j] == 'b':
            bc += 1
            edges[M*i+j+1][N*M+1] = 1
            edges[N*M+1][M*i+j+1] = 0

max_pair = max_flow(0, N*M+1)
wc -= max_pair
bc -= max_pair

print(max_pair*100+min(wc, bc)*10+abs(wc-bc))