Confluent2020A

/*
Author: Mehul Chaturvedi
*/

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

using ll = long long;
using pll = pair<ll, ll>;
#define f first
#define s second
#define vll vector<long long>
#define vvll vector<vector<ll>>
#define vset(v, n, val) v.clear(); v.resize(n, val)
#define rep(i, n) for (int i = 0, _n = (n); i < _n; i++)

vector<string> grid;
set<pll> vis;
ll n, m, k;

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

bool isOk(ll i, ll j) {
    return (i < n && j < m && i >= 0 && j >= 0 && grid[i][j] == '.');
}

void solve() {
    cin >> n;
    cin >> k;

    vset(grid, n, "");
    vis.clear();
    rep(i, n) cin >> grid[i];
    m = grid[0].size();

    queue<vll> q;
    //x, y, dis
    q.push({0, 0, 0});
    while (!q.empty()) {
        auto temp = q.front();
        q.pop();
        if (temp[0] == n - 1 && temp[1] == m - 1) {
            cout << ((temp[2] <= k) ? "Yes" : "No") << '\n';
            return;
        }
        if (vis.find({temp[0], temp[1]}) != vis.end()) continue;
        vis.insert({temp[0], temp[1]});

        rep(k, 4) {
            ll ni = temp[0] + dx[k];
            ll nj = temp[1] + dy[k];

            if (isOk(ni, nj)) q.push({ni, nj, temp[2] + 1});
        }
    }

    cout << "No" << '\n';
    return;
}

int main(int argc , char ** argv) {
    ios_base::sync_with_stdio(false) ;
    cin.tie(NULL) ;

    ll t = 1;
    while (t--) {
        solve();
    }

    return 0 ;
}