#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define srep(i,s,t) for (int i = s; i < t; ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
#define yn {puts("Yes");}else{puts("No");}
#define MAX_N 5005

int n;
vector<int> G[MAX_N];
int match[MAX_N];
bool used[MAX_N];

void add_edge(int u, int v){
    G[u].push_back(v);
    G[v].push_back(u);
}

bool dfs(int v){
    used[v] = true;
    for(int i = 0; i < G[v].size(); i++){
        int u = G[v][i], w = match[u];
        if(w < 0 || !used[w] && dfs(w)){
            match[v] = u;
            match[u] = v;
            return true;
        }
    }
    return false;
}

int bipartite_matching(){
    int res = 0;
    memset(match, -1, sizeof(match));
    for(int v = 0; v < n; v++){
        if(match[v] < 0){
            memset(used, 0, sizeof(used));
            if(dfs(v)){
                res++;
            }
        }
    }
    return res;
}

int dx[4] = {-1, 0, 1, 0};
int dy[4] = {0, -1, 0, 1};

int main() {
    int h, w;
    cin >> h >> w;
    n = MAX_N;
    string s[h];
    rep(i,h) cin >> s[i];
    int cntb = 0, cntw = 0;
    rep(i,h){
        rep(j,w){
            if(s[i][j] == 'b') cntb++;
            if(s[i][j] == 'w'){
                cntw++;
                rep(k,4){
                    int nx = i + dx[k];
                    int ny = j + dy[k];
                    if(nx < 0 || h <= nx || ny < 0 || w <= ny) continue;
                    if(s[nx][ny] != 'b') continue;
                    add_edge(i*w+j, nx*w+ny);
                }
            }
        }
    }


    int ans = 0;
    int tmp = bipartite_matching();
    ans += tmp * 100;
    cntb -= tmp;
    cntw -= tmp;
    ans += min(cntb,cntw) * 10;
    ans += cntb + cntw - min(cntb,cntw)*2;
    

    cout << ans << endl;
    return 0;
}