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

#define CPP_CAT(x,y) CPP_CAT_I(x,y)
#define CPP_CAT_I(x,y) x ## y
//#define CPP_STR(x) CPP_STR_I(x)
//#define CPP_STR_I(args...) #args
//#define ASSERT(expr...) assert((expr))

using i8 = int8_t;
using u8 = uint8_t;
using i16 = int16_t;
using u16 = uint16_t;
using i32 = int32_t;
using u32 = uint32_t;
using i64 = int64_t;
using u64 = uint64_t;
using f32 = float;
using f64 = double;
//using f80 = __float80;

constexpr i64 INF = 1'010'000'000'000'000'017LL;
constexpr i64 MOD = 1'000'000'007LL;
constexpr f64 EPS = 1e-12;
constexpr f64 PI = 3.14159265358979323846;
constexpr char EL[] = "\n";

#define FOR(i, start, end) for(i64 i = (start), CPP_CAT(i,xxxx_end)=(end); i < CPP_CAT(i,xxxx_end); ++i)
#define REP(i, n) FOR(i, 0, n)
#define all(x) (x).begin(),(x).end()
#define ALL(f,c,...) (([&](decltype((c)) cccc) { return (f)(std::begin(cccc), std::end(cccc), ## __VA_ARGS__); })(c))
#define UNIQUE(x) (x).erase(unique(all(x)), (x).end());
#define REPIT(x) for(auto it=(x).begin(), end=(x).end(); it!=end; ++it)
#define perm(c) sort(all(c)); for(bool c##p=1;c##p;c##p=next_permutation(all(c)))

template<typename T = i64>
T IN() { T x; cin >> x; return (x); }

template<typename C>
i64 SIZE(const C& c) { return static_cast<i64>(c.size()); }
template<typename T, size_t N>
i64 SIZE(const T(&)[N]) { return static_cast<i64>(N); }

template<typename T, typename U, typename Comp = less<>>
bool chmax(T& xmax, const U& x, Comp comp = {}) {
	if (comp(xmax, x)) {
		xmax = x;
		return true;
	}
	return false;
}
template<typename T, typename U, typename Comp = less<>>
bool chmin(T& xmin, const U& x, Comp comp = {}) {
	if (comp(x, xmin)) {
		xmin = x;
		return true;
	}
	return false;
}

void print() {
  cout << EL;
}
template <class Head, class... Tail>
void print(Head&& head, Tail&&... tail) {
  cout << head;
  if (sizeof...(tail) != 0) cout << " ";
  print(forward<Tail>(tail)...);
}
template <class T>
void print(vector<T> &vec) {
  for (auto& a : vec) {
	cout << a;
	if (&a != &vec.back()) cout << " ";
  }
  cout << EL;
}
template <class T>
void print(vector<vector<T>> &df) {
  for (auto& vec : df) {
	print(vec);
  }
}

struct ProconInit {
	static constexpr int IOS_PREC = 15;
	static constexpr bool AUTOFLUSH = false;

	ProconInit() {
		cin.tie(nullptr);
		ios::sync_with_stdio(false);
		cout << fixed << setprecision(IOS_PREC);
		if (AUTOFLUSH)
			cout << unitbuf;
	}
} PROCON_INIT;
#pragma endregion

signed solve()
{
	string s;
	cin >> s;
	ALL(reverse, s);

	while (0 < SIZE(s))
	{
		if (s[0] == 'r')
		{
			if (7 <= SIZE(s))
			{
				if (s.substr(0, 7) == "remaerd")
				{
					s = s.substr(7, SIZE(s) - 7);
					continue;
				}
			}
			if (6 <= SIZE(s))
			{
				if (s.substr(0, 6) == "resare")
				{
					s = s.substr(6, SIZE(s) - 6);
					continue;
				}
			}
		}
		else if (s[0] == 'm')
		{
			if (5 <= SIZE(s))
			{
				if (s.substr(0, 5) == "maerd")
				{
					s = s.substr(5, SIZE(s) - 5);
					continue;
				}
			}
		}
		else if (s[0] == 'e')
		{
			if (5 <= SIZE(s))
			{
				if (s.substr(0, 5) == "esare")
				{
					s = s.substr(5, SIZE(s) - 5);
					continue;
				}
			}
		}
		if (0 < SIZE(s))
		{
			print("NO");
			return 0;
		}
	}

	if (0 == SIZE(s))
		print("YES");
	else
		print("NO");
	return 0;


	//int idx = 0, len = SIZE(s);
	//while (idx < len)
	//{
	//	if (s[idx] == 'd')
	//	{
	//		if (idx + 7 <= len)
	//		{
	//			if (s.substr(idx, 7) == "dreamer")
	//			{
	//				if ((idx + 5 + 6 <= len && s.substr(idx + 5, 6) != "eraser") &&
	//					(idx + 5 + 5 <= len && s.substr(idx + 5, 5) != "erase"))
	//				{
	//					idx += 7;
	//					continue;
	//				}
	//			}
	//		}
	//		if (idx + 5 <= len)
	//		{
	//			if (s.substr(idx, 5) == "dream")
	//			{
	//				idx += 5;
	//				continue;
	//			}
	//		}
	//	}
	//	else if (s[idx] == 'e')
	//	{
	//		if (idx + 6 <= len)
	//		{
	//			if (s.substr(idx, 6) == "eraser")
	//			{
	//				idx += 6;
	//				continue;
	//			}
	//		}
	//		if (idx + 5 <= len)
	//		{
	//			if (s.substr(idx, 5) == "erase")
	//			{
	//				idx += 5;
	//				continue;
	//			}
	//		}
	//	}
	//	print("NO");
	//	return 0;
	//}
	//if (idx == len)
	//	print("YES");
	//else
	//	print("NO");
	//return 0;
}

#ifndef LOCALCODE
signed main()
{
	return solve();
}
#endif


Measured memory_bytes: 512