import java.util.*;

public class Main {
	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		
		String dream = "dream";
		String dreamer = "dreamer";
		String erase = "erase";
		String eraser = "eraser";
		
		str = str.replaceAll(eraser, "");
		str = str.replaceAll(erase, "");
		str = str.replaceAll(dreamer, "");
		str = str.replaceAll(dream, "");
		
		if(str.length() == 0) {
			System.out.println("YES");
		} else {
			System.out.println("NO");
		}
	}
} import java.util.*; util.* java public class Main {
	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		
		String dream = "dream";
		String dreamer = "dreamer";
		String erase = "erase";
		String eraser = "eraser";
		
		str = str.replaceAll(eraser, "");
		str = str.replaceAll(erase, "");
		str = str.replaceAll(dreamer, "");
		str = str.replaceAll(dream, "");
		
		if(str.length() == 0) {
			System.out.println("YES");
		} else {
			System.out.println("NO");
		}
	}
} Main public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		
		String dream = "dream";
		String dreamer = "dreamer";
		String erase = "erase";
		String eraser = "eraser";
		
		str = str.replaceAll(eraser, "");
		str = str.replaceAll(erase, "");
		str = str.replaceAll(dreamer, "");
		str = str.replaceAll(dream, "");
		
		if(str.length() == 0) {
			System.out.println("YES");
		} else {
			System.out.println("NO");
		}
	} main {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		
		String dream = "dream";
		String dreamer = "dreamer";
		String erase = "erase";
		String eraser = "eraser";
		
		str = str.replaceAll(eraser, "");
		str = str.replaceAll(erase, "");
		str = str.replaceAll(dreamer, "");
		str = str.replaceAll(dream, "");
		
		if(str.length() == 0) {
			System.out.println("YES");
		} else {
			System.out.println("NO");
		}
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String str = sc.nextLine(); str sc.nextLine() sc.nextLine sc String dream = "dream"; dream "dream" String dreamer = "dreamer"; dreamer "dreamer" String erase = "erase"; erase "erase" String eraser = "eraser"; eraser "eraser" str = str.replaceAll(eraser, "") str str.replaceAll(eraser, "") str.replaceAll str eraser "" str = str.replaceAll(erase, "") str str.replaceAll(erase, "") str.replaceAll str erase "" str = str.replaceAll(dreamer, "") str str.replaceAll(dreamer, "") str.replaceAll str dreamer "" str = str.replaceAll(dream, "") str str.replaceAll(dream, "") str.replaceAll str dream "" if(str.length() == 0) {
			System.out.println("YES");
		} else {
			System.out.println("NO");
		} str.length() == 0 str.length() str.length str 0 {
			System.out.println("YES");
		} System.out.println("YES") System.out.println System.out System System.out "YES" {
			System.out.println("NO");
		} System.out.println("NO") System.out.println System.out System System.out "NO" String args[] args public class Main {
	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		
		String dream = "dream";
		String dreamer = "dreamer";
		String erase = "erase";
		String eraser = "eraser";
		
		str = str.replaceAll(eraser, "");
		str = str.replaceAll(erase, "");
		str = str.replaceAll(dreamer, "");
		str = str.replaceAll(dream, "");
		
		if(str.length() == 0) {
			System.out.println("YES");
		} else {
			System.out.println("NO");
		}
	}
} public class Main {
	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		
		String dream = "dream";
		String dreamer = "dreamer";
		String erase = "erase";
		String eraser = "eraser";
		
		str = str.replaceAll(eraser, "");
		str = str.replaceAll(erase, "");
		str = str.replaceAll(dreamer, "");
		str = str.replaceAll(dream, "");
		
		if(str.length() == 0) {
			System.out.println("YES");
		} else {
			System.out.println("NO");
		}
	}
} Main
import java.util.*;

public class Main {
	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		
		String dream = "dream";
		String dreamer = "dreamer";
		String erase = "erase";
		String eraser = "eraser";
		
		str = str.replaceAll(eraser, "");
		str = str.replaceAll(erase, "");
		str = str.replaceAll(dreamer, "");
		str = str.replaceAll(dream, "");
		
		if(str.length() == 0) {
			System.out.println("YES");
		} else {
			System.out.println("NO");
		}
	}
}
