#include <bits/stdc++.h>
using namespace std;
const bool debug = false;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  string s[8];
  for (int i = 0; i < 8; i++) {
    cin >> s[i];
  }
  int r = 0, col = 0;
  for (int i = 0; i < 8; i++) {
    int c = 0;
    for (int j = 0; j < 8; j++) {
      if (s[i][j] == 'B') c++;
    }
    if (c == 8) r++;
  }
  for (int i = 0; i < 8; i++) {
    int c = 0;
    for (int j = 0; j < 8; j++) {
      if (s[j][i] == 'B') c++;
    }
    if (c == 8) col++;
  }
  if (r == 0 and col == 0) {
    cout << 0;
    return 0;
  }
  if (r == 8 or col == 8) {
    cout << 8;
    return 0;
  }
  cout << r + col;
}
