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

#define int long long  

signed main() {  
    ios::sync_with_stdio(false);
    cin.tie(nullptr);  

	int n, m, k;
	cin >> n >> m >> k;

	vector<int> a(m + 1);
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			char c;
			cin >> c;
			if (c == 'A') {
				a[j]++;
			}
		}
	}
	for (int i = 1; i <= m; i++) {
		a[i] = (n - a[i]) * a[i];
	}

	int ans = 0;
	for (int t = 1; t < (1LL << m); t++) {
		for (int i = 0; i < m; i++) {
			if ((t >> i & 1) && a[i + 1] >= k) {
				ans++;
				break;
			}
		}
	}

	cout << ans << "\n";

    return 0;
}