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

#define rep(i,s,n) for (int i = (int)s; i < (int)n; i++)
#define ll long long
#define ld long double
#define pb push_back
#define eb emplace_back
#define All(x) x.begin(), x.end()
#define Range(x, i, j) x.begin() + i, x.begin() + j
#define lbidx(x, y) lower_bound(x.begin(), x.end(), y) - x.begin()
#define ubidx(x, y) upper_bound(x.begin(), x.end(), y) - x.begin()
#define llbidx(x, y, z) lower_bound(x.begin(), x.end(), z) - lower_bound(x.begin(), x.end(), y) // 二要素間の距離
#define deg2rad(deg) ((((double)deg)/((double)360)*2*M_PI))
#define rad2deg(rad) ((((double)rad)/(double)2/M_PI)*(double)360)
#define Find(set, element) set.find(element) != set.end()
#define Decimal(x) printf("%.10f\n", x) // 小数点を10桁まで表示
// debug用
#define PrintVec(x) for (auto elementPrintVec: x) { cout << elementPrintVec << " "; } cout << "\n";
#define debug(x) cerr << #x << ": " << (x) << "\n";
#define endl "\n"
// gcj print用
#define Case(x) printf("Case #%d: ", x);

typedef pair<int, int> PI;
typedef pair<ll, ll> PLL;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<vector<vector<int>>> vvvi;
typedef vector<ll> vl;
typedef vector<vector<ll>> vvl;
typedef vector<vector<vector<int>>> vvvl;
typedef vector<PI> vpi;
typedef vector<vector<PI>> vvpi;
typedef vector<vector<vector<PI>>> vvvpi;
typedef vector<PLL> vpl;
typedef vector<vector<PLL>> vvpl;
typedef vector<vector<vector<PLL>>> vvvpl;

int POWINT(int x, int n) {
  int ret = 1;
  while (n > 0) {
    if (n & 1) ret *= x;
    x *= x;
    n >>= 1;
  }
  return ret;
};

ll POWLL(ll x, int n) {
  ll ret = 1;
  while (n > 0) {
    if (n & 1) ret *= x;
    x *= x;
    n >>= 1;
  }
  return ret;
};

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

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

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);

  string S;
  cin >> S;

  bool ok = true;

  while (S.size()) {
    char ch = S.back(); S.pop_back();
    if (ch == 'r') {
      if (S.size() < 5) {
        ok = false;
        break;
      }

      bool is_eraser = true;
      if (S.size() >= 5) { // erase
        string tmp = "";
        rep(i, 0, 5) {
          tmp += S[S.size()-5+i];
        }

        if (tmp == "erase") {
          is_eraser = true;
        } else {
          is_eraser = false;
        }
      } else {
        is_eraser = false;
      }

      bool is_dreamer = true;
      if (S.size() >= 6) {
        string tmp = "";
        rep(i, 0, 6) {
          tmp += S[S.size()-6+i];
        }

        if (tmp == "dreame") {
          is_dreamer = true;
        } else {
          is_dreamer = false;
        }
      } else {
        is_dreamer = false;
      }

      if (is_eraser) {
        rep(i, 0, 5) {
          S.pop_back();
        }
      } else if (is_dreamer) {
        rep(i, 0, 6) {
          S.pop_back();
        }
      } else {
        ok = false;
        break;
      }
    } else if (ch == 'e') {
      if (S.size() < 4) {
        ok = false;
        break;
      }

      string tmp = "";
      rep(i, 0, 4) {
        tmp += S[S.size()-4+i];
      }

      if (tmp == "eras") {
        rep(i, 0, 4) {
          S.pop_back();
        }
      } else {
        ok = false;
        break;
      }
    } else if (ch == 'm') {
      if (S.size() < 4) {
        ok = false;
        break;
      }

      string tmp = "";
      rep(i, 0, 4) {
        tmp += S[S.size()-4+i];
      }

      if (tmp == "drea") {
        rep(i, 0, 4) {
          S.pop_back();
        }
      } else {
        ok = false;
        break;
      }
    } else {
      ok = false;
      break;
    }
  }

  if (ok) {
    cout << "YES" << endl;
  } else {
    cout << "NO" << endl;
  }

  return 0;
};


Measured memory_bytes: 640