#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cmath>
#include<cctype>
#include<math.h>
#include<string>
#include<string.h>
#include<stack>
#include<queue>
#include<vector>
#include<utility>
#include<set>
#include<map>
#include<stdlib.h>
#include<iomanip>

using namespace std;

#define ll long long
#define ld long double
#define EPS 0.0000000001
#define INF 1e9
#define LINF (ll)INF*INF
#define MOD 1000000007
#define rep(i,n) for(int i=0;i<(n);i++)
#define loop(i,a,n) for(int i=a;i<(n);i++)
#define all(in) in.begin(),in.end()
#define shosu(x) fixed<<setprecision(x)

#define int ll //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

typedef vector<int> vi;
typedef vector<string> vs;
typedef pair<int,int> pii;
typedef vector<pii> vp;

int gcd(int a, int b){
    if(b==0) return a;
    return gcd(b,a%b);
}
int lcm(int a, int b){
    return a*b/gcd(a,b);
}

//ford-fulkerson
//O(FE)
#define MAX_V 10000
struct edge{ int to,cap,rev;};
vector<edge> G[MAX_V];
bool used[MAX_V];
void add_edge(int from, int to, int cap){
    G[from].push_back((edge){to,cap,G[to].size()});
    G[to].push_back((edge){from,0,G[from].size()-1});
}
int dfs(int v, int t, int f){
    if(v == t)return f;
    used[v] = true;
    for(int i = 0; i < G[v].size(); i++){
        edge &e = G[v][i];
        if(!used[e.to] && e.cap > 0){
            int d = dfs(e.to,t, min(f,e.cap));
            if(d > 0){
                e.cap -= d;
                G[e.to][e.rev].cap += d;
                return d;
            }
        }
    }
    return 0;
}

int max_flow(int s, int t){
    int flow = 0;
    while(1){
        memset(used,0,sizeof(used));
        int f = dfs(s, t, INF);
        if(f == 0)return flow;
        flow += f;
    }
}

signed main(void) {
    int n,m;
    cin >> n >> m;
    vs s(n);
    rep(i,n)cin >> s[i];
    int w = 0, b = 0;
    int dx[] = {0,1,0,-1};
    int dy[] = {1,0,-1,0};
    rep(i,n)rep(j,m)if(s[i][j] != '.'){
        int from = i*m+j;
        if(s[i][j] == 'w')rep(k,4){
            int x = i + dx[k];
            int y = j + dy[k];
            if(x < 0 || x >= n || y < 0 || y >= m || s[x][y] == '.')continue;
            int to = x*m+y;
            add_edge(from+1,to+1,1);
        }
        if(s[i][j] == 'w') add_edge(0,from+1,1),w++;
        else add_edge(from+1,n*m+1,1),b++;
    }
    int num = max_flow(0,n*m+1);
    //cout << w << " " << b << " " << num << endl;
    int ans = num * 100;
    w -= num, b -= num;
    ans += 10 * min(w,b);
    ans += max(w,b) - min(w,b);
    cout << ans << endl;

}