#include<iostream>
#include<cstring>
using namespace std;
const int SIZE = 55;
const int NODE = SIZE * SIZE;

int row, col;
char ch[SIZE][SIZE];

void read() {
    cin >> row >> col;
    for (int i = 0; i < row; ++i) {
        for (int j = 0; j < col; ++j) {
            cin >> ch[i][j];
        }
    }
}


bool dfs(int curr, int L2R[NODE], int R2L[NODE], bool visited[NODE], int nNode, bool adj[NODE][NODE]) {
    if (curr == -1) return true;
    visited[curr] = true;
    for (int i = 0; i < nNode; ++i) {
        if (!adj[curr][i]) continue;
        int next = R2L[i];
        if (next != -1 && visited[next]) continue;
        if (dfs(next, L2R, R2L, visited, nNode, adj)) {
            L2R[curr] = i;
            R2L[i] = curr;
            return true;
        }
    }
    return false;
}

int maxMatch(int nNode, bool adj[NODE][NODE]) {
    int cnt = 0;
    int L2R[NODE];
    int R2L[NODE];
    memset(L2R, -1, sizeof(L2R));
    memset(R2L, -1, sizeof(R2L));
    
    for (int i = 0; i < nNode; ++i) {
        bool visited[NODE] = {};
        cnt += dfs(i, L2R, R2L, visited, nNode, adj);
    }

    return cnt;
}


void work() {
    int cntBlack = 0;
    int cntWhite = 0;
    
    static bool adj[NODE][NODE];
    memset(adj, 0, sizeof(adj));

    for (int r = 0; r < row; ++r) {
        for (int c = 0; c < col; ++c) {
            if (ch[r][c] == '.') continue;

            cntBlack += ch[r][c] == 'b';
            cntWhite += ch[r][c] == 'w';
            
            int selfId = r * row + c;
            
            static int dr[] = {-1, 0, 1, 0};
            static int dc[] = {0, 1, 0, -1};
            for (int i = 0; i < 4; ++i) {
                int nr = r + dr[i];
                int nc = c + dc[i];

                if (!(0 <= nr && nr < row && 0 <= nc && nc < col)) continue;
                if (ch[nr][nc] == '.') continue;

                int oppId = nr * row + nc;

                if ((r + c) % 2 == 0) {
                    adj[selfId][oppId] = true;
                }
                else {
                    adj[oppId][selfId] = true;
                }
            }
        }
    }

    int cntMatch = maxMatch(row * col, adj);
    cntBlack -= cntMatch;
    cntWhite -= cntMatch;

    cout << cntMatch * 100 + min(cntBlack, cntWhite) * 10 + max(cntBlack, cntWhite) - min(cntBlack, cntWhite) << endl;
}


int main() {
    read();
    work();
    return 0;
}