import std.conv, std.functional, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.container, std.math, std.numeric, std.range, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


class BMatch {
  int n;
  int[][] g;
  int[] to;
  bool[] flg;
  this(int n) {
    this.n = n; g = new int[][n]; to = new int[n]; flg = new bool[n];
  }
  void addEdge(int u, int v) {
    g[u] ~= v; g[v] ~= u;
  }
  bool augment(int u) {
    foreach (v; g[u]) if (!flg[v]) {
      flg[v] = true;
      if (to[v] == -1 || augment(to[v])) {
        to[u] = v; to[v] = u; return true;
      }
    }
    return false;
  }
  int solve() {
    int ret;
    to[] = -1;
    foreach (u; 0 .. n) if (to[u] == -1) {
      flg[] = false;
      if (augment(u)) ++ret;
    }
    return ret;
  }
}


int M, N;
string[] S;

void main() {
  try {
    for (; ; ) {
      M = readInt();
      N = readInt();
      S = new string[M];
      foreach (x; 0 .. M) {
        S[x] = readToken();
      }
      
      int[2] cnt;
      foreach (x; 0 .. M) foreach (y; 0 .. N) {
        if (S[x][y] != '.') {
          ++cnt[(x + y) % 2];
        }
      }
      
      auto bm = new BMatch(M * N);
      foreach (x; 0 .. M) foreach (y; 0 .. N) {
        if (S[x][y] != '.') {
          if (x > 0 && S[x - 1][y] != '.') {
            bm.addEdge((x - 1) * N + y, x * N + y);
          }
          if (y > 0 && S[x][y - 1] != '.') {
            bm.addEdge(x * N + (y - 1), x * N + y);
          }
        }
      }
      const res = bm.solve();
      
      int ans;
      ans += res * 100;
      ans += (min(cnt[0], cnt[1]) - res) * 10;
      ans += abs(cnt[0] - cnt[1]) * 1;
      writeln(ans);
    }
  } catch (EOFException e) {
  }
}