#include <atcoder/all>

#include <bits/stdc++.h>

using namespace std;
#define SZ(x) (int) (x).size()
#define REP(i, n) for(int i = 0; i < (n); i++)
#define FOR(i, a, b) for(auto i = (a); i < (b); i++)
#define For(i, a, b, c) \
	for(auto i = (a); i != (b); i += (c))
#define REPR(i, n) for(auto i = (n) -1; i >= 0; i--)
#define ALL(s) (s).begin(), (s).end()
#define so(V) sort(ALL(V))
#define rev(V) reverse(ALL(V))
#define uni(v) v.erase(unique(ALL(v)), (v).end())
#define eb emplace_back

typedef unsigned long long ull;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<bool> vb;
typedef vector<vi> vvi;
typedef vector<vll> vvll;
typedef pair<int, int> PI;
typedef pair<ll, ll> PL;
const double EPS = 1e-6;
const int MOD = 1e9 + 7;
const int INF = (1 << 30);
const ll LINF = 1e18;
const double math_PI = acos(-1);

template<typename T>
vector<T> make_v(size_t a) {
	return vector<T>(a);
}

template<typename T, typename... Ts>
auto make_v(size_t a, Ts... ts) {
	return vector<decltype(make_v<T>(ts...))>(
		a, make_v<T>(ts...));
}

template<typename T, typename V>
typename enable_if<is_class<T>::value == 0>::type fill_v(
	T& t, const V& v) {
	t = v;
}

template<typename T, typename V>
typename enable_if<is_class<T>::value != 0>::type fill_v(
	T& t, const V& v) {
	for(auto& e: t) fill_v(e, v);
}

template<class T>
bool chmax(T& a, const T& b) {
	if(a < b) {
		a = b;
		return true;
	}
	return false;
}

template<class T>
bool chmin(T& a, const T& b) {
	if(a > b) {
		a = b;
		return true;
	}
	return false;
}

template<typename S, typename T>
istream& operator>>(istream& is, pair<S, T>& p) {
	cin >> p.first >> p.second;
	return is;
}

template<typename T>
istream& operator>>(istream& is, vector<T>& vec) {
	for(T& x: vec) is >> x;
	return is;
}

template<typename T>
string join(vector<T>& vec, string splitter) {
	stringstream ss;
	REP(i, SZ(vec)) {
		if(i != 0) ss << splitter;
		ss << vec[i];
	}
	return ss.str();
}

template<typename T>
ostream& operator<<(ostream& os, vector<T>& vec) {
	os << join(vec, " ");
	return os;
}
using namespace atcoder;

int main() {
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	int H, W;
	cin >> H >> W;
	vector<string> S(H);
	cin >> S;
	vvi ID(H, vi(W));
	int rock = 0;
	REP(i, H) {
		REP(j, W) {
			if(S[i][j] == 'r') {
				ID[i][j] = rock;
				rock++;
			}
		}
	}
	int hole = 0;
	REP(i, H) {
		REP(j, W) {
			if(S[i][j] == 'h') {
				ID[i][j] = hole;
				hole++;
			}
		}
	}

	mf_graph<int> G(rock + hole + 2);
	int s = rock + hole;
	int t = s + 1;
	REP(i, rock) {
		G.add_edge(s, i, 1);
	}
	REP(i, hole) {
		G.add_edge(rock + i, t, 1);
	}
	REP(i, H) {
		vi pre;
		REP(j, W) {
			if(S[i][j] == 'r') {
				pre.push_back(ID[i][j]);
			}
			if(S[i][j] == 'h') {
				for(auto id: pre) {
					G.add_edge(id, rock + ID[i][j], 1);
				}
				pre.clear();
			}
		}
		pre.clear();
		REPR(j, W) {
			if(S[i][j] == 'r') {
				pre.push_back(ID[i][j]);
			}
			if(S[i][j] == 'h') {
				for(auto id: pre) {
					G.add_edge(id, rock + ID[i][j], 1);
				}
				pre.clear();
			}
		}
	}
	REP(j, W) {
		vi pre;
		REP(i, H) {
			if(S[i][j] == 'r') {
				pre.push_back(ID[i][j]);
			}
			if(S[i][j] == 'h') {
				for(auto id: pre) {
					G.add_edge(id, rock + ID[i][j], 1);
				}
				pre.clear();
			}
		}
		pre.clear();
		REPR(i, H) {
			if(S[i][j] == 'r') {
				pre.push_back(ID[i][j]);
			}
			if(S[i][j] == 'h') {
				for(auto id: pre) {
					G.add_edge(id, rock + ID[i][j], 1);
				}
				pre.clear();
			}
		}
	}
	if(G.flow(s, t) == rock) {
		cout << "Yes" << endl;
	} else {
		cout << "No" << endl;
	}
	return 0;
}