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#include<bits/stdc++.h>
#define ALL(X)        X.begin(),X.end()
#define FOR(I,A,B)    for(int (I) = (A); (I) <= (B); (I)++)
#define FORW(I,A,B)   for(int (I) = (A); (I) < (B);  (I)++)
#define FORD(I,A,B)   for(int (I) = (A); (I) >= (B); (I)--)
#define CLEAR(X)      memset(X,0,sizeof(X))
#define SIZE(X)       int(X.size())
#define CONTAINS(A,X) (A.find(X) != A.end())
#define PB            push_back
#define MP            make_pair
#define X             first
#define Y             second
using namespace std;
template<typename T, typename U> ostream& operator << (ostream& os, const pair<T, U> &_p) { return os << "(" << _p.X << "," << _p.Y << ")"; }
template<typename T> ostream& operator << (ostream &os, const vector<T>& _V) { bool f = true; os << "["; for(auto v: _V) { os << (f ? "" : ",") << v; f = false; } return os << "]"; }
template<typename T> ostream& operator << (ostream &os, const set<T>& _S) { bool f = true; os << "("; for(auto s: _S) { os << (f ? "" : ",") << s; f = false; } return os << ")"; }
template<typename T, typename U> ostream& operator << (ostream &os, const map<T, U>& _M) { return os << set<pair<T, U>>(ALL(_M)); }
typedef signed long long slong;
typedef long double ldouble;
typedef pair<int,int> pii;
const slong INF = 1000000100;
const ldouble EPS = 1e-9;

template<class TH> void _dbg(const char *sdbg, TH h){cerr<<sdbg<<"="<<h<<"\n";}
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
  while(*sdbg!=',')cerr<<*sdbg++;cerr<<"="<<h<<","; _dbg(sdbg+1, a...);
}

#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

typedef vector<int> vi;

int N, K;

const int MAXN = 1042;
int F[MAXN][MAXN];

int dx[4] = {-1,0,1,0};
int dy[4] = {0,1,0,-1};

int check(const vector<pii> &v) {
    vi ok(K,0);
    int sum = 0;
    FOR(it,1,K) {
        int fail = 1;
        FORW(i,0,K) {
            pii x = v[i];
            if(!ok[i]) {
                FORW(j,0,4) {
                    if(F[x.X+dx[j]][x.Y+dy[j]]) {
                        ok[i] = 1;
                        F[x.X][x.Y] = 1;
                        sum++;
                        fail = 0;
                        break;
                    }
                }
            }
        }
        if(fail) break;
    }
    FORW(i,0,K) {
        pii x = v[i];
        F[x.X][x.Y] = 0;
    }
    if(sum != K) return 0;
    return 1;
}

void solve()
{
    cin >> N >> K;
    FOR(i,1,N) {
        string s;
        cin >> s;
        FORW(j,0,N) {
            if(s[j] == '#') {
                F[i][j+1] = 1;
            }
        }
    }

    vector<pii> v;
    FOR(i,1,N) {
        FOR(j,1,N) {
            if(!F[i][j]) {
                v.PB({i,j});
            }
        }
    }

    int m = SIZE(v);
    slong ans = 0;
    FORW(a,0,m) {
        FORW(b,a,m) {
            if(K == 1) {
                if(b > a) break;
            }
            else if(a == b) continue;
            FORW(c,b,m) {
                if(K <= 2) {
                    if(c > b) break;
                }
                else if(c == b) continue;
                FORW(d,c,m) {
                    if(K <= 3) {
                        if(d > c) break;
                    }
                    else if(c == d) continue;

                    vector<pii> tmp = {v[a], v[b], v[c], v[d]};
                    if(check(tmp)) {
                        ans++;
                    }
                }
            }
        }
    }

    cout << ans << "\n";
}

int main()
{
    ios_base::sync_with_stdio(0);
    solve();
}