#include <bits/stdc++.h>
using namespace std;

int main() {
    int N, M;
    cin >> N >> M;

    vector<string> S(N);
    for (auto &s : S) cin >> s;

    vector<int> cnt(M);

    for (int i = 0; i < N; i++) {
        for (int j = 0; j < M; j++) {
            if (S[i][j] == 'o')
                cnt[j]++;
        }
    }

    int ans = 0;

    for (int i = 0; i < N; i++) {
        bool hasEvent = false;
        bool unique = true;

        for (int j = 0; j < M; j++) {
            if (S[i][j] == 'o') {
                hasEvent = true;

                if (cnt[j] != 1)
                    unique = false;
            }
        }

        if (hasEvent && unique)
            ans++;
    }

    cout << ans << '\n';
}